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Causes of Homosexuality: A Christian Appraisal of the Data

Andrew J. Sodergren, M.S.

John Paul II Institute for Studies on Marriage and Family


           This paper discusses some of the recent scientific findings on the causes of homosexuality in the context of a Christian anthropology.  After reviewing the major findings in the empirical literature, the discussion focuses on how such an anthropology can account for these findings without compromising the traditional Christian ethical teaching that homosexual acts are intrinsically immoral and the homosexual inclination is objectively disordered.  Of particular importance here are notions of original sin, fallen nature, the sexual difference, and the virtue of chastity. 

Causes of Homosexuality:  A Christian Appraisal of the Data

           Debates over the morality of homosexual acts and same-sex unions inevitably contain some inferences and remarks about the supposed causes of homosexual inclinations.  Likewise, researchers who examine the causes of homosexuality are often unable to refrain from commenting on the ethical debate.  Thus, these issues seem intertwined, at least in the minds of many well-intentioned people.  This interlinking, however, tends to result in misunderstanding and in fallacious assumptions on the sides of both ethicists and scientists because of a lack of understanding across disciplines.  For instance, many in the ethical debate over homosexuality hold that not only are homosexual acts always immoral but also the very disposition is in some way morally disordered.  On the other hand, scientists often oppose such a view and hold that a homosexual orientation is morally neutral.  They marshal empirical evidence of a biological basis for the homosexual orientation, proving that it is “natural” and should therefore be embraced and lived out by those who experience it.  In this paper I will attempt to steer a path through this tangled forest.  I will begin by providing an overview of the major empirical findings on the causes of homosexuality.  I will then attempt to show that a Christian anthropology can account for these findings without compromising a firm ethical stance on homosexual acts and inclinations.

Research on the Etiology of Homosexuality

            The most publicized research studies on the causes of homosexuality have been those examining the role of genetics.  Indeed, a number of studies have attempted to assess the heritability of the homosexual orientation.  The primary way of examining the genetic contribution to a given behavior or disposition such as sexual orientation is through twin studies.  The premise is that by comparing monozygotic (MZ) twins (who share 100% of their genetic code), dizygotic (DZ) twins and biological siblings (who both share approximately 50% of their genetic code), and adopted siblings (who have none of their genetic code in common), researchers can glean an understanding of whether a trait is heritable and to what extent (Billings & Beckwith, 1993).  However, in order to truly assess the effects of genes, one has to control or neutralize the contribution of environmental factors in the development of the characteristic in question.  Such environmental factors could include anything from position in the womb, maternal nutrition, and the hormonal milieu of the uterine environment to post-natal care, early illnesses, parenting style, family constellation, education, socialization, and so forth.  These influences can have profound effects not only on a person’s behavior but even on their biological make-up.  Thus, researchers are coming to recognize that the hard division of nature—nurture is no longer tenable.  It is always a “both—and”, especially in traits as complicated as sexual orientation.  It is important to note that several of the factors listed above pertain to the prenatal environment.  In this period of development, the environment can have profound effects on the organism, and this will be discussed further below.

           In the most desirable type twin study, researchers examine MZ twins who were separated at birth and reared apart.  This is considered the ideal in behavioral genetics.  As the reasoning goes, since such twins have the same genetic code but are reared in different environments, any behavioral similarities they manifest likely have a strong genetic basis.  Unfortunately, these situations are rare, and they are extremely so if the trait being studied is itself uncommon.  Homosexuality is just such a case.  A great deal of research in recent years has shown that roughly 2-3% of men in the United States are homosexual (Fay, Turner, Klassen, & Gagnon, 1989; Rogers & Turner, 1991; Leigh, 1993; Billy, Tanfer, Grady, & Klepinger, 1993; Seidman & Reider, 1994; Black, Gates, Sanders, & Taylor, 2000).  The figure is even smaller for women, approximately 1-2% (Diamond, 1993; Laumann, Michael, Gagnon, & Michaels, 1994; Wellings, Field, Johnson, & Wadworth, 1994).  Thus, locating MZ twins who were separated at birth and of whom at least one twin developed a homosexual orientation is unfeasible.  Moreover, such a twin study (MZ twins reared separately) does not in fact neutralize the environment to the extent that researchers surmise.  The reason for this is that MZ twins, even if they are separated from the moment of birth forward, still shared the same, profoundly influential environment for the previous nine months.  Thus, every twin study, no matter how elegant in design, cannot fully tease apart the effects of genes and environment.

           Researchers try to cope with these difficulties by comparing MZ twins who were reared together with other sibling pairs such as DZ twins, normal biological siblings, and adopted siblings with no biological relation between them.  Bailey and Pillard (1991) followed this general paradigm by examining family patterns of adult males with homosexual orientation who had either a MZ twin, DZ twin, or adopted brother.  These researchers found a concordance rate (if one twin was homosexual, the other was as well) of 52% among the male MZ twins who were reared together in the study.  The figure for female MZ twins was 48%.  Likewise, male DZ twins reared together showed a concordance rate of 22% (16% for women) but this was not significantly different from the rate for adoptive brothers (Bailey & Pillard, 1991).  What this study shows is that there may be a genetic component to homosexuality, but there appear to be substantial environmental factors as well.  Why else would the concordance rate among MZ twins be so much less than 100% and why would there be any concordance at all among adoptive brothers? 

           Though far from conclusive, this study by Bailey and Pillard was highly influential.  Several such twin studies followed, and, taken together, the lowest concordances found for homosexuality among MZ twins was 47% for men and 48% for women (Bailey, Dunne, & Martin, 2000).  However, the samples of twins included in these studies were largely recruited through advertising in gay or lesbian publications.  This creates the possibility of “ascertainment bias”.  In other words, “twins deciding whether to participate in a study clearly related to homosexuality probably considered the sexual orientation of their co-twins before agreeing to participate” (Bailey et al., 2000, p. 533).  This non-random sampling, of course, would result in biased data.  Bailey, Dunne, and Martin (2000) overcame this methodological weakness by using a large sample (N=4901) of adult twins recruited from the Australian Twin Registry.  In that study, the researchers identified 27 pairs of male twins in which at least one of the men was homosexual.  However, only 3 of these pairs were concordant (both twins were homosexual).  Thus, 3 of 27 pairs of male twins (approximately 11%) were concordant on homosexuality in this systematic study.  Likewise, only 3 of 22 pairs of female twins (approximately 14%) were concordant.  These researchers conclude, “These rates are significantly lower than the respective rates for the two largest prior twin studies of sexual orientation….  This suggests that concordances from prior studies were inflated because of concordance-dependent ascertainment bias” (Bailey, et al., 2000, p. 533).  They go on to state,

           Consistent with several studies of siblings… we found that sexual orientation is familial.  In contrast to most prior twin studies of sexual orientation, however, ours did not provide statistically significant support for the importance of genetic factors for that trait (p. 534).

           This does not rule out the possibility that there is a genetic component to homosexuality but rather suggests that “sexual orientation is inherited, if at all, in a complex manner” (Bailey & Pillard, 1995, p.144, emphasis added).  

           A second line of research examining the supposed genetic basis for homosexuality employs the molecular analysis of blood samples from relatives of homosexuals and a method called linkage analysis, which maps genes onto chromosomal regions, to identify the specific gene or genes that influence sexual orientation.  Based on evidence that “gay men have more homosexual uncles and cousins through the maternal line than on the paternal side” some researchers have attempted to identify an X-linked gene that influences male sexual orientation (Rahman & Wilson, 2003, p. 1342).  Hamer, Hu, Magnuson, Hu, and Pattatucci, (1993) initially reported findings consistent with this hypothesis that implicated the chromosomal region Xq28 in the heritability of male homosexuality.  A similar though weaker relationship was reported later by members of the same research group (Hu et al., 1995).  However, the methods used in these studies and therefore the reported results have been called into question.  Risch, Whleeler, and Keats (1993) criticized the research design and statistical methods used by Hamer et al. (1993) and asserted that their conclusions might not be supported by the data.  In addition, Rice et al. (1999) attempted to replicate the previously reported link between Xq28 and male homosexuality using similar methods in independently conducted genetic studies, but their results did not support the Xq28 hypothesis.  Indeed, these researchers stated,

           It is unclear why our results are so discrepant from Hamer’s original study.  Because our study was larger than that of Hamer et al., we certainly had adequate power to detect a genetic effect as large as was reported in that study.  Nonetheless, our data do not support the presence of a gene of large effect influencing sexual orientation at position Xq28 (Rice et al., 1999, p. 668). 

           These issues were again revisited in the journal Science in 1999 (Hamer et al., 1999; Rice, Risch, & Ebers, 1999).  It is clear from these articles that because scientists are treading on new methodological ground, there is no simple solution to this question.  The methods being used in these studies have not been tested and verified in studying a trait as complex as sexual orientation.  Hamer et al. (1999) defended their approach and attempted to meta-analyze four studies in this area concluding that they collectively support the Xq28 hypothesis.  However, Rice, Risch, & Ebers (1999) pointed out that if only those studies carried out by independent investigators are considered, which is necessary to reduce potential biases, no researchers outside Hamer’s own group has found support for the Xq28 hypothesis: “Thus, the conclusion remains that the original studies of Hamer and colleagues are not replicated” (Rice, Risch, & Ebers, 1999, p. 806). 

           A study conducted by Bailey et al. (1999) also examined the hypothesis that homosexuality is the result of an X-linked gene using more stringent standards in recruitment analysis than many previous studies.  Three sampling techniques were utilized:  recruitment from an HIV clinic, a gay pride parade, and through homophile publications.  All participants were interviewed about familial patterns of non-heterosexuality.  Only the sample attained through magazine advertisement knew of this purpose of the study.  The researchers found a rate of occurrence of homosexuality among brothers of a homosexual male ranging from 7.3% to 9.7%.  This suggests a modest familial (not necessarily genetic) component to the origin of male homosexuality.  Bailey et al. (1999) also found a slight increase in the appearance of female homosexuality among sisters of gay men.  However, the familial patterns of homosexuality observed in this study did not support the Xq28 hypothesis.  “This study found no evidence that male sexual orientation is influenced by an X-linked gene” (Bailey et al., 1999, p. 84). 

            One final study worth mentioning was recently conducted by Mustanski, DuPree, Nievergelt, Bocklandt, Schork, and Hamer (2005).  Using blood samples of 456 individuals from 146 unrelated families, the researchers conducted for the first time a search of the entire human genome for a genetic basis to male homosexuality.  Though three gene regions resulted in elevated values, none were large enough to generate a statistically significant result.  In addition, they found no evidence of a link to the Xq28 region.  Thus, as stated above, research into the genetic basis for homosexuality, taken as a whole, is inconclusive.  While there may be a modest heritability to such an orientation, the existence of an overriding gay gene seems highly unlikely at this time.

            Another biologically based line of research bearing on the question of the etiology of homosexuality deals with the pre-natal environment.  As already alluded to, fetal development is a remarkably crucial time in the development of the human organism.  In particular, brain systems develop rapidly during this period and are quite sensitive to hormonal and other biochemical influences.   Normally in a male child, his testes will begin producing testosterone during the fetal period which masculinizes various body structures and systems.  (Girls produce androgens as well from their adrenal glands, though usually in much smaller quantities than boys who produce them in their testes and adrenals.)  Besides the obvious differences such as genitalia, musculature, etc., this masculinzation process affects the development of various brain structures and, thus, their functions (see chap. 8 of Baron-Cohen, 2003).  The development of the child in the womb can also be influenced by the mother’s hormone levels.  It has been hypothesized that abnormal hormone levels or other deviations during the fetal period could be responsible for the development of non-heterosexual orientations (for reviews, see Mustanski, Chivers, & Bailey, 2002; Rahman & Wilson, 2003). 

            Researchers have made various attempts to study such an effect upon the development of homosexual orientations.  While for ethical reasons, experimenters cannot manipulate the hormonal milieu of the prenatal environment in humans, they can study cases in which such abnormalities occur naturally to see if a homosexual orientation is more likely to result.   In addition, a certain amount can be learned from animal studies.  Finally, somatic and neuropsychological variables known to be strongly affected by prenatal hormones can be compared in adults to see if they differ according to sexual orientation.

            All of these methods have been utilized, and it appears that in some respects, female homosexuals appear to have experienced increased prenatal androgenization compared to heterosexuals (more masculine auditory systems and waist-to-hip ratio, higher salivary testosterone levels, less desire to give birth, etc.).  Likewise, on some measures homosexual men appear to have been less androgenized than heterosexual men (more female-like pubertal onset, weight, height, cognitive spatial abilities, and language abilities; higher rates of non-right handedness).  However, on other measures homosexual men appear hypermasculine, i.e. exposed to greater quantities of androgens (more masculine relative finger lengths, possibly larger penises [according to two studies: Nedoma & Freund, 1961; Bogaert & Hershberger, 1999], and possibly hypermasculine auditory systems [see McFadden, 2002]).  Some differences in the size and shape of certain adult brain structures have also been identified across sexual orientation categories, but it is unknown whether these neural differences cause or are consequent upon homosexual lifestyles.  After all the brain is a “plastic” structure that changes throughout life in response to one’s genetic/biological endowment, experiences, and behaviors.  Thus, the data on the role of prenatal androgens are very complex, and no scholarly consensus exists on how to integrate and interpret them.  If abnormal androgen levels are what drive these differences, they appear to affect males and females differently since homosexual men and homosexual women do not always differ from their heterosexual counterparts on the same variables.  Moreover, the data on homosexual men are mixed.  Rahman and Wilson (2003) put forward the hypothesis that perhaps a genetic factor in some men alters the distribution of androgen receptors in various brain structures.  Thus, when exposed to prenatal androgens at whatever level, the result will be that some brain structures will be more masculinized than normal and others will be less masculinzed than normal because of the redistribution of the receptors.  While this makes a good deal of sense, the research has not yet shown this to be the case.

            Perhaps the most well replicated phenomenon related to the causes of homosexuality is the “fraternal birth order effect”.  To put it simply, “Several studies, which collectively examined over 7000 subjects, have shown that homosexual men have, on average, a greater number of older brothers than do comparable heterosexuals” (Ellis and Blanchard, 2001, p. 543).  Thus, something about being born later in a line of several brothers seems to increase the likelihood of male homosexuality.  Researchers believe that the fraternal birth order effect per se is not the ultimate causal factor of male homosexuality in these cases but that there is some other mechanism in place that mediates the effect.  However, what this causal mechanism is is still highly debated.  Most favor a biological explanation such as a fluctuation in prenatal androgens or increased maternal immune system response related to multiple, successive male pregnancies.  Another possibility with mixed empirical support suggests that maternal stress, which could increase with the births of multiple sons, may alter fetal development in such a way as to increase the likelihood of a homosexual orientation.  Stress hormones are in fact produced in the adrenal glands (and are therefore, androgens or at least androgen-like) and can interfere with normal fetal development.  Other explanations for the fraternal birth order effect are psychosocial in nature and posit such potential causes as ostracization of boys by older brothers or increased early sex play among boys with several older brothers (see James, 2004a; 2004b).  Presently, however, the fraternal birth order effect remains largely unexplained in the absence of any overwhelmingly conclusive evidence.  Moreover, it is important to note that according to researchers only 14.8% to 15.2% of homosexual men can attribute their orientation to this effect (Cantor, Blanchard, Paterson, & Bogaert, 2002).  Though it is a well established and easily identifiable phenomenon connected with the genesis of male homosexuality, the fraternal birth order effect does not appear to be the primary cause of homosexuality in the majority of gay men.  Nothing analogous to this effect has been found in women. 

            In light of the foregoing, it is important to recall that sexual orientation does not emerge immediately upon conception and birth but takes time to develop throughout childhood, adolescence, and even adulthood.  Thus, there is a great deal of room for experience to affect this process.  Consequently, researchers investigating the various factors discussed above agree that rather than causing homosexual orientation directly these influences likely precipitate a set of pre-homosexual traits and dispositions that in turn increases the likelihood of adult homosexuality (Bailey & Zucker, 1995; Dunne, Bailey, Kirk, & Martin, 2000).  The term coined for this is childhood gender nonconformity (CGN), which simply refers to a certain conglomeration of sex atypical traits (physical, psychological, and behavioral features).  CGN is known to be consistently associated with later homosexual orientations as well as many of the biological and familial factors discussed above (Bailey & Zucker, 1995).  However, since not everyone with CGN develops an adult homosexual orientation, there must be some environmental influences that contribute to such a development.  These could include for instance failed relationships with one’s parents and/or peers.  Indeed, classic psychodynamic theory held that male homosexuality was primarily caused by a maladaptive family pattern in which the father is weak and distant and the mother is over-controlling (roughly the reverse is posited for females).  While there has been very little data in the last 20 years supporting these specific claims, research does emphasize the importance of relationships in the development of sexual orientation.  For instance, an interesting study by Landolt, Bartholomew, Saffrey, Oram, and Perlman (2004) examined the relationship between CGN and rejection from parents and peers in a sample of 191 gay and bisexual men.  They found, “Gender nonconforming behavior in childhood was associated with maternal, paternal, and peer rejection” among these gay and bisexual men (p. 124).  Another recent study, though methodologically weak, found that among a sample of Catholic seminarians, those admitting a homosexual orientation also reported “more emotional distance from their fathers than heterosexual seminarians” (Seutter & Rovers, 2004, p. 46). 

            Bem (1996; 2000) proposed a model of sexual orientation development which he dubbed the “exotic becomes erotic” theory.  He proposes that biological variables influence childhood temperaments which in turn affect a child’s degree of gender conformity.  A child who has nonconforming traits and behaviors feels him/herself to be different from peers.  This “feeling different” from same-sex peers can evolve into an erotic attraction in adolescence:

           An individual’s protracted and sustained experience of feeling different from same- or opposite-sex peers throughout childhood and adolescence produces a correspondingly sustained physiological arousal that gets eroticized when the maturational, cognitive, and situational factors coalesce to provide the critical defining moment (Bem, 2000, p. 539).

           While these various accounts all have merit to them and a certain ring of truth, one aspect of the development of a homosexual orientation not explicitly tapped in any of them is the role of child sexual abuse (CSA) and other early sexual experiences.  There seems to be a link between CSA perpetrated by men (or older males) against boys that predisposes these boys to later identify as homosexual.  Indeed, one reviewer states, “The effects of sexual victimization on male children, placed in the context of the prevailing concept of masculinity, include mental disorders, the probability of becoming rapists and incest offenders as adults, and the development of homosexual identification” (Vander Mey, 1988, p. 61).  Several studies support this claim.  For instance, Finkelhor (1984) found a statistically significant relationship between CSA victimization and later homosexual activity in adulthood (cited in Dimock, 1988).  In a study of 25 adult males who had been sexually abused in childhood, the majority of these men experienced “masculine identity confusion” characterized by “confusion regarding sexual preference and… male roles” (Dimock, 1988, p. 208).  Homosexual feelings and/or behaviors were common among these men.  Noting that “the literature reports that there may be a significant number of gay men who have been sexually abused as children,” Schwartz (1994) presented clinical data from eight men who had been victims of CSA.  “Six of the eight men identified themselves as homosexual in their sexual identity; two were heterosexual.  Of the two heterosexuals, one continuously questioned his sexual orientation” (Schwartz, 1994, p. 182).  Likewise, Johnson & Shrier (1985) compared 40 male victims of CSA and an age-matched control group and found that 47.5% of the CSA victims went on to develop a homosexual orientation and another 10% became bisexual.  “The study group identified themselves as currently homosexual nearly seven times as often and bisexual nearly six times as often as the control group” (Johnson & Shrier, 1985, p. 374). 

           These small studies finding an increased likelihood of homosexual identification in male victims of CSA are corroborated by at least twelve more recent and systematic ones that have all documented elevated rates of CSA among homosexual men (Saewyc, Pettingell, & Skay, 2004; Kalichman et al., 2004; Ratner et al., 2003; Garcia, Adams, Friedman, & East, 2002; Dolezal & Carballo-Diéguez, 2002; Tomeo et al., 2001; Paul et al., 2001; Krahé et al., 2001; Paris et al., 1995; Doll et al., 1992; Baier et al., 1991; Haverkos, Bukoski, & Amsael, 1989; for reviews see Relf, 2001; Holmes & Slap, 1998).  For instance, using a nonclinical sample of 942 participants, Tomeo et al. (2001) found that 46% of homosexual men had been sexually abused as a child by a man.  This was significantly greater than the 7% rate found among heterosexual men in that study.  Among a sample of 307 Latin American men who have sex with men (MSM), Dolezal and Carballo-Diéguez (2002) observed “that early sexual contact [with males] is common among these men. 

           Fifty-nine percent had had some sexual/genital contact prior to their 13th birthday.  In the majority of those cases, they had a partner who was at least 4 years older than they were” (p. 169-170).  Finally, in a systematic study of 2881 MSM, Paul et al. (2001) found that one fifth had experienced CSA.  They state,

           Our study confirms and extends prior research indicating high prevalence levels of childhood sexual abuse (CSA) among MSM.  Such prevalence levels might be higher if we had elicited data about experiences involving non-contact sexual victimization (i.e., sexual exposure or exhibitionism).  Overall, these men’s CSA experiences were characterized by high levels of penetrative sex, physical force, and perceptions of these events as distressing (Paul et al., 2001, p. 575).

           Interestingly, some research suggests that boys who have gender nonconforming traits such as effeminate physical features are rated as more attractive by adults than a control group of typical boys (Zucker, Wild, Bradley, & Lowry, 1993). 

           Even in cases where such young men and boys do not report the experience as abusive, early sexual contact with other males is common prior to identifying oneself as gay.  For instance, Dawood et al. (2000) found that one third of their sample of gay men with gay brothers had engaged in sexual activity with their siblings in childhood.  “Among the 21 participants who indicated that some form of sex play occurred, levels of activity included touching and mutual masturbation (N=16), giving or receiving fellatio (N=9), and anal intercourse (N=4)” (p. 161).  A recent study of 961 Dutch gay and bisexual men “found that 68% of respondents engaged in their first same-sex experience before coming-out” (Schindhelm & Hospers, 2004, p. 585).  Another study found that 58% of homosexual and bisexual men came to their sexual identity through a sex-centered sequence, i.e. one in which same-sex activity preceded their identification as gay or bisexual (Dubé, 2000).  In a study comparing homosexual men and women, researchers discovered that homosexual men were more likely to pursue sex before identifying themselves as gay, whereas for women the context of their homosexual identity development was more emotionally oriented (Savin-Williams & Diamond, 2000). 

           This last finding raises an interesting but challenging issue:  sexual orientation in men and women is markedly different and develops in divergent ways.  Summarizing research in this area, Diamond (2003) states,

           Women show greater variability than men in the age at which they consciously question their sexuality, and the age at which they pursue their first same-gender sexual contact….  Also, women place less emphasis on the sexual component of their lesbian or bisexual identification, both during and after the questioning process…, and are more likely to report that their sexuality is fluid and chosen versus fixed and biologically given… (p. 185).

           Thus, for men, a homosexual orientation seems to involve a strong inclination to engage in sexual activity with other men.  Whereas, for women the question of sexual orientation is much more caught up in affectional bonding and is more often a matter of conscious choice than an irresistible urge. 

            This review of the research shows us that many known factors (and there are likely still more unknown factors) are implicated in the development of homosexuality, but no one factor seems powerful enough to trump them all.  Rather, the adult homosexual has probably arrived at that orientation through a complex, idiosyncratic combination of biological, experiential, and volitional factors.  This process seems clearly divergent for men and women and likely differs from individual to individual among gays and among lesbians. 

Homosexuality & Christian Anthropology

            The purpose of the foregoing discussion was to clarify the state of scientific research on the causes of homosexuality.  It is important for moralists and those responsible for public policy to be well-informed on these issues.  However, as mentioned in this paper’s introduction, these data are sometimes misused in ethical debates over homosexuality.  Primarily, some argue on the basis of science that homosexuality has a strong, inborn, biological origin.  Regardless of what combination of factors actually produced the orientation, it is believed to arise in the person without any act of the person’s choosing.  Since this disposition is apparently innate, then it must be in a sense natural.  After all, it seems to arise quite naturally in those who experience it.  If, therefore, a homosexual orientation arose by nature’s choosing – or perhaps even God’s choosing – to act on such an inclination would be to act in accord with one’s nature.  The person so inclined who adopts a homosexual lifestyle is simply behaving in an authentic way:  he/she is being true to him/herself.  The Congregation for the Doctrine of the Faith summarized this view by saying, “Some people conclude that their tendency is so natural that it justifies in their case homosexual relations within a sincere communion of life and love analogous to marriage insofar as such homosexuals feel incapable of enduring a solitary life” (CDF, 1975, no. 8, emphasis added). 

            This is a legitimate argument that deserves a response.  However, Christians who hold the traditional view “that homosexual acts are intrinsically disordered and can in no case be approved of” (CDF, 1975, no. 8) and that the homosexual orientation itself is “objectively disordered” (CCC, no. 2358) are left in a difficult position.  Some Christians seeking to avoid implying that God wills people to be homosexual and creates this orientation in them deny the role of biological causes in the etiology of homosexuality.  This is problematic for several reasons.  First of all, it is not true to scientific research which, despite inconclusiveness and other difficulties, does suggest that there are biological components (genes, prenatal effects, etc.) to homosexuality.  To deny the role of biology, then, encourages the popular view that Christianity is somehow opposed to science or that to follow Christian doctrine, one must renounce scientific rigor.  This, of course, is patently false.  Secondly, this denial is often motivated by the misguided fear that if one were to admit a biological predisposition to homosexuality, there would no longer be any basis for condemning homosexual acts.  Thirdly, arguing in this way – that homosexuality is in no way biologically inherited – leads one to commit the same mistake committed by those on the other side, namely a misuse of the concept “nature”.  This is precisely where a counter-argument should begin.

            Those who argue that homosexual inclinations are “natural” utilize a problematic understanding of nature that needs to be challenged.  This understanding of nature refers to that which is innate and unchosen within a person.  “I did not choose to be the way I am.”  “I discovered my homosexuality within me.”  Moreover, a certain normative quality is attributed to this nature such that it can and should dictate my actions.  Nature as such is good, or at least neutral in respect to ethics, so the modern mentality holds that whatever I am naturally disposed to do I should do as long as it does not involve violating the rights of others. 

           A Christian anthropology, however, comes to very different conclusions about “nature”.  Human nature, in a Christian sense, does also have a normative content to it.  As the Congregation for the Doctrine of the Faith says, “There can be no true promotion of man’s dignity unless the essential order of his nature is respected” (CDF, 1975, no. 3).  In creating the world, God inscribed a certain order in it.  Thus, the true nature of things and their fulfillment can be understood only in light of God’s design.  This is especially salient when we are speaking of desires that arise within the human heart for Christian revelation recognizes the reality of original sin.  At the start of human history, our first parents rebelled against God’s plan and by their action, brought disorder into the world:  “Adam and Eve committed a personal sin, but this sin affected the human nature that they would then transmit in a fallen state” (CCC, no. 404).  The Fathers of the Church taught that human nature is one and thus all human beings participate in the same nature.  Thus, when our first parents marred their likeness to God through sin, the whole human family was affected by it.  Thus, the human nature that each human being inherits is disordered.  Original sin

           is a deprivation of original holiness and justice, but human nature has not been totally corrupted: it is wounded in the natural powers proper to it; subject to ignorance, suffering, and the dominion of death; and inclined to sin – an inclination to evil that is called “concupiscence” (CCC, no. 405).

           Every evil in the world is traceable back to this fundamental disruption at the beginning of time.  Indeed, another crucial aspect of Christian anthropology is that human nature involves a unity of body and soul such that the human person is not wholly identifiable with either taken separately but exists as a composite of the two.  In other words, the body and the soul are intrinsically united. 

           The unity of soul and body is so profound that one has to consider the soul to be the “form” of the body: i.e., it is because of its spiritual soul that the body made of matter becomes a living, human body; spirit and matter, in man, are not two natures united, but rather their union forms a single nature (CCC, no. 365).

           Therefore, when we say that original sin has wounded human nature, this includes both physical and spiritual effects.  In this way, the doctrine of original sin can account for every sort of genetic or biological defect, disease, or disorder as well as all kinds of human suffering and inclinations to do evil.  With this understanding of fallen human nature, a Christian anthropology would have no difficulty accommodating research (past or future) implicating a substantial inherited component to homosexuality.

            Clearly, this understanding of original sin is essential when we are speaking of the moral quality of human inclinations.  Because of original sin, a certain disorder resides in the human heart such that one often desires that which is contrary to the moral law.  Therefore, even if homosexual inclinations are entirely inherited, this does not mean that they necessarily correspond with human nature in the original sense, as God intended it.  Moreover, as Christ made clear in his preaching, it is the original, created order that has normative weight to it, not this transitory fallen state: 

           Some Pharisees approached him, and tested him, saying, “Is it lawful for a man to divorce his wife for any cause whatever?” He said in reply, “Have you not read that from the beginning the Creator ‘made them male and female’ and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’? So they are no longer two, but one flesh. Therefore, what God has joined together, no human being must separate” (Mt 19.3-6).

           Thus, the inclinations that arise in the human heart must be tested according to objective moral norms because the human nature we encounter in this age of history, though wounded by sin, is still called to the same norms of behavior intended by God “from the beginning.”  Why?  Because God created us “out of love for love” (John Paul II, 1981, no. 11); His wise, loving plan permeates all of created reality.  Therefore, to follow the norms given to us by our Creator and Redeemer is in no way an imposition or alienation but a call to happiness.  The moral law given to us by God is a blueprint by which human beings can achieve their fulfillment.  This implies another fundamental truth of Christian anthropology:  human nature is wounded, but it is not totally corrupted.  Man still has freedom.  Though weakened by sin and prone to misuse, the human person still possesses the ability to make free moral choices and, by cooperating with God’s grace, grow in holiness and maturity. 

           Freedom is the power, rooted in reason and will, to act or not to act, to do this or that, and so to perform deliberate actions on one’s responsibility.  By free will one shapes one’s own life.  Human freedom is a force for growth and maturity in truth and goodness; it attains its perfection when direct toward God, our beatitude (CCC, no. 1731).

           The proper, beatifying use of freedom requires God’s grace.  Only with His help can we properly see the truth and act in accord with it.  Thankfully, God desires all men to be saved and abundantly supplies the means for it to happen.

           If a person finds himself or herself inclined to a homosexual lifestyle, this certainly is a cross to bear because it means that the person has “a more or less strong tendency ordered toward an intrinsic moral evil and thus the inclination itself must be seen as an objective disorder” (CDF, 1986, no. 3).  Only in light of original sin does it make sense to say that someone could inherit an “objective disorder”.  Recall that the research on homosexuality does not conclusively show that it is inherited, but there is no need on the basis of Christian teaching to deny this possibility.  Moreover, society commonly recognizes that certain disordered propensities are inborn in some people.  For instance, there is acceptance for the notion that various pathological personality traits are heritable as well as predispositions for various addictions such as alcoholism.  Yet, these characteristics are not normalized but still held to be deviations from normal, “healthy” humanity.  In light of this, there is no justification for a priori accepting homosexual inclinations and homosexual acts as morally upright without serious rational reflection in the light of objective moral norms.

            Such a discussion, however, would be incomplete without mention of the problem of sexual identity.  Because of the language of sexual orientation prevalent in contemporary culture, there is a great deal of confusion regarding sexual identity in the fundamental sense.  Christian anthropology recognizes that there are two genders:  male and female.  This maleness or this femaleness is ontologically grounded in the human person such that the person is always one or the other and this sexual differentiation affects all areas of life.  Nonetheless, man and woman share the same human nature, though they live it and express it in two irreducibly different ways.

           The importance and the meaning of sexual difference, as a reality deeply inscribed in man and woman, needs to be noted. “Sexuality characterizes man and woman not only on the physical level, but also on the psychological and spiritual, making its mark on each of their expressions”. It cannot be reduced to a pure and insignificant biological fact, but rather “is a fundamental component of personality, one of its modes of being, of manifestation, of communicating with others, of feeling, of expressing and of living human love”.  This capacity to love – reflection and image of God who is Love – is disclosed in the spousal character of the body, in which the masculinity or femininity of the person is expressed (CDF, 2004, no. 8).

           Because of original sin, deviations of this sexual difference can and do occur, but there are just that – deviations.  The problem with the language of sexual orientation is that it tends to separate sexual desire from sexual identity (the basic sexual difference of male and female).  Though one is a man, one’s sexuality need not be inclined toward women and vice versa.  This implies that all orientations are on the same anthropological and ethical standing, which the Church recognizes as false.  A homosexual inclination is “objectively disordered” (CCC, no. 2358).  This is only understood when one sees one’s biological sex and the purposes inscribed in it as fundamentally intrinsic to one’s personal identity.  In other words, sexual identity consists in being male or female, and within these two irreducible ways of being human, there is no room for a multiplicity of sexual orientations.  The fact that such orientations exist is, once again, a result of original sin.  The way to overcome the power of sin is not to normalize all the deviations and disorders that it produces but to persevere in seeking and living by the truth with the unfailing help of God’s grace.

           Homosexual persons are called to chastity.  By the virtues of self-mastery that teach them inner freedom, at times by the support of disinterested friendship, by prayer and sacramental grace, they can and should gradually and resolutely approach Christian perfection (CCC, no. 2359).

           Rather than embracing one’s disordered desires with reckless abandon, they must be submitted to the truth, and thus gradually transformed into dispositions of virtue.  Only in doing so, can one’s fallen human nature slowly grow toward its proper perfection bringing with it true freedom and happiness.  Accordingly, persons with homosexual tendencies cannot find true happiness in embracing their disordered orientation as their core identity and the guiding light of their lifestyle, but rather they are called to live their sexuality in integrity precisely as a man or as a woman according to the truth of the divine plan.  This truth is rooted in God Himself Who created us, holds us in being, and bears our destiny within Himself.  Thus, to seek chastity according to God’s plan is not an imposition of arbitrary norms but the inner condition of attaining the fulfillment desired by every human heart.  Though it may be a long difficult road, as the late Karol Wojtyla stated, “Chastity is the sure way to happiness” (Wojtyla, 1960, p. 172).


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Version: 25th May 2005

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