Can Intersex Persons be Ordained as Catholic Priests?

John Perry
Saturday 5 June 2021
  1. Introduction and Hypothesis
  2. Fields of Study
  3. Discussion
  4. Conclusion

1. Introduction and Hypothesis

The Christian church has a long history of limiting certain roles to men. Before the twentieth century virtually no denominations didn’t segregate clerical positions by sex, and the majority still do today. Last century was one of powerful movements for equality, including gender equality, but the fact that Christian practice seems to run counter to such movements is not our focus here, important as they are. This puzzle is concerned with a different twentieth century development: advances in genetics that show sexing mammals is a more complicated business than it appears. Some mammals, including some humans, are not biologically male but neither are they not not male. Such persons are among those called ‘intersex’ by physicians. What happens when intersex persons belong to a church that segregates by sex? Can they be ordained?

To study this, I narrowed my focus: I investigated the Roman Catholic sacrament of holy orders (ordination), reading such sources as the Catechism and various encyclical since the 1970s, and also studied recent findings from biology and genetics about the phenomenon of intersexuality. In Catholic practice, it is bishops who decide whether to ordain a given candidate. The rule is plain: only ordain men. But without further guidance, the bishop would not know how to apply this rule to intersex individuals, because the rule presupposes that human sex is simpler than it is. Based on this introductory reading, my working hypothesis was: Recent findings in biology suggest that the “only ordain men” rule, thus stated, cannot be applied with certainty (as the Church says is required) to any candidate for ordination.

2. Fields of Study

2.1 Liturgical Studies

  1. This puzzle is not about the possibility of ordaining women as Catholic priests, but there aren’t many sources about Christians who happen to be intersex. Nearly all the relevant sources in sacramental theology deal with the issue of sex and gender via the possibility of women’s ordination. The most relevant of these are the Catechism of the Catholic Church (CCC 1992), John Paul II’s encyclical Mulieris Dignitatem (MD 1988), and the CDF’s Inter Insigniores (II 1976).
  2. In the Church’s first centuries, as soon as the process of ordination had any sort of systemization, leadership roles were all held by men. There is some debate about before the time of systemization, e.g. the founding of the Philippian church (Acts 16).
  3. Thomas Aquinas’s theology of the sacraments includes a point of special relevance here. He distinguishes two criteria for sacraments: legality and validity.
    • A sacrament which lacks legality still “works” as it were. For example, a bishop should not ordain a young boy, but if he did, the boy would become a genuine priest. Thomas says the same about serious physical deformities: if the bishop ordains a man without a nose (Thomas’s own example!), the noseless priest is still a priest because his ordination was valid—even if technically illegal (ST supp 39.6).
    • By contrast, an invalid sacrament does not work. After an invalid marriage, the couple is still unmarried; after an invalid consecration of the Eucharist, the bread is not Christ’s body; and after an invalid ordination, the candidate remains a layperson.
  1. Thomas says that the sex of the candidate is a matter of validity, not only legality: “Wherefore even though a woman were made the object of all that is done in conferring Orders, she would not receive Orders” (ST supp 39.1). In post-Vatican II discussions of whether women could be ordained as Catholic priests, the Vatican used this very point in reply, effectively saying, Even if the pope himself wanted to, it is impossible; it wouldn’t “work”.
  2. Canon law states: a “male [vir] alone receives sacred ordination validly” (Code of Canon Law 1024).
  3. The 2004 instruction for Mass says: “the Church requires certainty regarding the conditions necessary for the validity of the sacraments” (Redemptionis Sacramentum 50).
  4. The Vatican has been clear that many reasons that were previously offered for opposing women’s ordination were unquestionably sexist; such ‘reasons’ must be abandoned because the Church teaches that bigotry is wrong. Nonetheless, sex segregation is not always sexist. It could be benign.
  5. Over the past 30 years or so, the Vatican has spoken against what it calls gender theory, seeing it as incompatible with natural law because it conceives of gender as a choice disconnected from biological sex. One of the rare places that they address intersex phenomena is in such documents, notably ‘Male and female he created them’: Towards a Path of Dialogue on the Question of Gender Theory in Education (M&F 2019). (Calling this gender theory is ill-defined. The Vatican’s opposition would be better put as, “Some findings of scholars who work within gender studies are incompatible with…”)

2.2 History of Science (including applications of primitive biology within law and society)

  1. The phenomenon of intersex people has been known since antiquity, including among the Greek, Egyptian, and Israelite-Jewish cultures. These were informed by the science of the day; in the West, there were two rival theories (Hare 2015, 81).
    • One was the one-seed theory, associated with Pythagoras; Plato and Aristotle held this view. The male parent contributed the form of new life, and the female added the blood and flesh. This was why menstruation would cease during pregnancy: all the blood was diverted to ‘growing’ the embryo out of the seed. The sex of the offspring was dependent on the quality of the mother’s care.
    • The second, the Hippocratic school, developed the two-seed theory, both partners contributing one. The quality of each seed would determine various characteristics, such as intelligence and the sex of the offspring, either male, female, or androgynous (an intersex person).
  1. The Bible and Talmud seem to take the one-seed theory for granted, with rare exceptions (van der Horst 1996). The New Testament authors only used the word eunuch, which is ambiguous but presumably included intersex persons (DeFranza 2015, 205). In the Talmud, there are four different terms for various sorts of intersex conditions (Hare 2015, 87-88; Cohen 1999).
  2. As biological knowledge about sex developed during the twentieth century, societal rules and norms also developed. A notable example is athletics. In the 1950s, the International Olympic Committee (IOC) started requiring visual examination by a team of physicians, in case some athletes were males pretending to be females. Later, the IOC started using a blood test for the SRY gene, which typically, but not always, indicates maleness. More recently, they settled on a policy which restricted women athletes based on their levels of testosterone, on the theory that it is primarily testosterone that gives men a competitive advantage (Dreger 2018), which some scientists dispute (Boye, Pielke, and Tucker 2018).

2.3 Biology and Genetics

  1. In modern genetics, the simplest way of sexing humans is via the typical chromosomal pattern; XX for females, XY for males.
  2. Looking deeper, animal sex is first determined by a gene called the sex-determining gene. In the mammalian world, the sex-determining gene is called SRY, which triggers other genes (SOX9, DMRT, FOXL2, etc.), which in turn causes the differences we all are accustomed to when distinguishing the sexes, like narrower hips among human males. All of this means that biologists can sex mammals using (Austriaco 2013):
    • hormone ratios,
    • chromosomes,
    • gonads (the presence or absence of ovaries and testes),
    • genitalia (the presence or absence of a clitoris and a penis),
    • secondary characteristics (among humans, vocal register and breast/hip shape).

The above interrelate, e.g. hip shape is partly a function of hormone ratios. This means if you think that what matters when sexing a human is hip shape, you are implicitly saying that hormones matter too.

  1. But what if those markers are pointing in different directions? There are dozens of such variations that count as intersex traits (Hare 2015). I list only three here:
    • Swyer syndrome: a chromosomally XY person develops female traits.
    • 46,XX male: a chromosomally XX person appears otherwise male.
    • Persistent Mullerian duct syndrome (PMDS): an individual has both sets of gonads (testes and ovaries), and may even, rarely, be fertile.

With these three conditions, and others like them, hormone ratios and secondary characteristics can vary, making them unreliable sex markers taken by themselves.

  1. Assessing the frequency of such traits is more complicated (Reardon 2016) and subject to much dispute (Fausto-Sterling 2000; Sax 2002).
    • Some scholars, who estimate 0.02% of people are intersex, restrict the word to those cases where phenotypic sex is inconsistent with chromosomal sex; i.e. cases of the body not looking ‘normal’.
    • Others estimate as many as 1.7% of people are intersex. They are including cases that are not readily apparent (e.g., people who have an extra X chromosome, but appear otherwise typical).
    • Anecdotally, physicians and others involved in treatment prefer the narrower concept, and biologists prefer the more expansive.

3. Discussion

Benign Sex Segregation?

Remember our question: can intersex persons be ordained as Catholic priests? Let’s start with the assertion that not every form of sex segregation is sexist. Could that be true? Sure. We already touched on sex classification of athletes. The IOC rules are not obviously sexist and could even enhance equality. In medicine, are there any reasons, apart from misogyny or misandry, that someone would prefer a male or female doctor? Yes. One reason could be that patients judge they receive better medical care from someone with whom they can identify or who shares some of the same symptoms. Perhaps a woman wants a gynecologist who knows what it is like to experience menstruation or how a pap smear feels.

Likewise, with clothing. Within most fashion cultures, men and women differ in the style they prefer to wear. That is not what I mean here; that would be gender-segregated clothing. I mean clothes that are tailored differently due to biological differences of male and female anatomy. Are there sound reasons for sex-segregated clothes? Yes. Certain articles are sex specific, due to the differing secondary sex characteristics of females and males, including hip and breast shape. Illegitimate (e.g. sexist) reasons usually imply an advantage, or preference, for one or another class. Classes of clothing, however, imply none of these things, notwithstanding the existence of certain items, such as uncomfortable heeled shoes for women, which are gender distinctions.

So, not every instance of sex segregation is sexist, but notice that in each of these three examples we were able to specify a telos behind the practice that justified the segregation. Athletics depends on competitive contests; sometimes having women compete with other women leads to better contests. Good medical care depends, partly, on the ability to empathize by sharing symptoms; sometimes when doctor and patient share the same sex, it leads to better care. If one of the purposes for clothes is that they fit well, it is good that clothes are ‘segregated’ too.

What is the analogous telos for ordination? CCC (Catechism of the Catholic Church) only pushes the question back a step: “The Lord Jesus chose men (viri) to form the college of the twelve apostles… For this reason the ordination of women is not possible” (1577). So, why did Jesus so choose; what was his reason?

Mulieris Dignitatem

In support of the above claim, CCC appeals to two documents, Mulieris Dignitatem (MD) and Inter Insigniores (II) both of which initially appear to do no better. Reading on in those two, they do eventually give somewhat more concrete reasons for the limit. MD roots its reason in complimentary spousal love. II roots its reason in the need for sacramental signs to ‘naturally resemble’ what they signify. Both documents explicitly reject patristic and medieval prejudices, such as reasons based on Aristotle’s view that females were flawed males.

In MD, the reason for sex segregation among priests is because only with a male priest could the Eucharist “express the relationship between man and woman, between what is ‘feminine’ and what is ‘masculine’” (MD, no. 26). Thus far, the pope sounds like he is making a gender distinction: masculine (paternal, husbandly) love works in a certain sort of way, and feminine (maternal, wifely) love works another way. The pope does, in fact, believe that—genders are complimentary—but he doesn’t mean that precisely here, or he doesn’t mean only that here. In the most relevant passage of MD, he connects this to the establishment of the Eucharist. There he writes, the Twelve, who are all males, “alone receive the sacramental charge, ‘Do this in remembrance of me.”’

We find ourselves at the very heart of the Paschal Mystery, which completely reveals the spousal love of God. Christ is the Bridegroom because “he has given himself”: his body has been “given”, his blood has been “poured out.” … The “sincere gift” contained in the Sacrifice of the Cross gives definitive prominence to the spousal meaning of God’s love. As the Redeemer of the world, Christ is the Bridegroom of the Church… Christ is united with this “body” as the bridegroom with the bride. (MD, no. 26)

Note the allusions to his definition, elsewhere in MD, of coitus in Genesis 2-3, including ejaculation; namely, blood and semen are both ‘poured out’. He continues: “This is clear and unambiguous when the sacramental ministry of the Eucharist, in which the priest acts ‘in persona Christi’, is performed by a man” (MD, no. 26). So far, this is not a complete argument, for John Paul II has not said that in persona Christi acts are impossible for a woman or an intersex person, only that if performed by a man, these acts would be “clear and unambiguous.” Hypothetically, a woman could still perform them adequately. But that is not the pope’s view. He seeks a more unequivocal No; he therefore cites the aforementioned Inter Insigniores.

Inter Insigniores

Inter Insigniores (II) says, to be effective, sacraments must naturally resemble what they signify, perceptibly and easily recognizably. This passage seems to raise more questions than it answers. Resemble in what way? Does it mean, for example, the wine used for the Eucharist today must look perceptibly like the wine used by Jesus at the Last Supper? Or, does it mean that the wine must resemble blood, because that is the object of signification? The only clue is provided in the attached footnote: “‘For since a sacrament is a sign, there is required in the things that are done in the sacraments not only the res but the signification of the res,’ recalls Saint Thomas, precisely in order to reject the ordination of women” (II, n.18).

If we ask what Thomas meant by this, we encounter more trouble. He meant that women are unable to naturally resemble man’s superiority over women; however, II explicitly disavows such arguments, which it attributes to “the undeniable influence of prejudices unfavorable to woman” (II, 3). Having relinquished the superiority argument, the document leaves itself without any sort of natural resemblance argument—other than simply repeating Jesus’ gender, which it does over and over.

Male and Female He Created Them

One of the rare places that the Church speaks of intersex phenomena is in documents opposing gender theory, recently in Male and Female He Created Them (M&F):

Efforts to go beyond the constitutive male-female sexual difference, such as the ideas of ‘intersex’ or ‘transgender’, lead to a masculinity or femininity that is ambiguous, even though (in a self-contradictory way), these concepts themselves actually presuppose the very sexual difference that they propose to negate or supersede. (M&F, 25)

Intersex and transgender are quite different concepts, which M&F seems to conflate here. I do not follow how intersex presupposes “the very sexual difference that [gender theorists] propose to negate.” It could be that this document is speaking of them in an idiosyncratic, non-scientific sense. Without more explanation, I don’t know how to interpret this passage. Many modern languages do not have words distinguishing sex from gender; sometimes such languages use the English loanword gender as a workaround to make the distinction. Perhaps we are seeing some linguistic confusion in this document, or perhaps it is pointing to a deeper confusion. For now, count this passage as anomalous data.

The Reason behind the Rule?

Recall that in reading these documents, we were in search of the telos behind the ‘only ordain men’ rule. Have we found an answer? Indeed, we have found four different answers.

Telos 0. There is no real telos (reason behind the rule), or at least not one that humans have access to, because all we can know is that Jesus chose the Twelve. ‘Why?’ is beside the point.

Telos 1. The telos is to ‘perceptibly and recognizably’ resemble ‘man’s superiority’. (Aquinas)

Telos 2. The telos behind the segregation is spousal love (i.e., coital imagery). (MD)

Telos 3. Looking to biology for answers is to speak at cross purposes. Theological sex is not necessarily the same as biological sex. Only the former counts in canon law.

To the bishop with the intersex ordinand, our puzzle is not an idle curiosity. He really needs an answer, and, if he remembers the 2004 instructions for Mass, he needs certainty, because anything to do with eucharistic validity requires it (2.1.e, above).

If Telos 0 is right, the bishop cannot act to ordain anyone because no one knows for sure what the Twelve had in common. They could have had XY chromosomes, functioning testes, and narrow hips but it is far from certain. Who knows? St Mark could have had Klinefelter syndrome (a sex chromosome abnormality) and no one, least of all him, would have known. If we are supposed to be imitating Jesus’ choice, we need to know what choice to imitate. Knowing ‘why?’ cannot be beside the point; it is essential.

Telos 1 seems to be ruled out by showing “prejudices unfavorable to woman,” which Inter Insigniores disavows.

Telos 2 seems the most consistent with recent documents, especially John Paul II’s Theology of the Body, MD, and his earlier writings as Karol Wojtyla. If the telos of the rule is to better convey the spousal love and coital imagery that lies at the heart of the Eucharist, how—if at all—does it help our bishop? That depends on how literally the coital symbol/analogy (the pope uses both terms) is supposed to function. The root of the analogue, i.e. coitus, requires the male to have a penis capable of penetration and functioning testes (‘giving’ and ‘pouring out’), but this is only the source of the image. For the consecration of the Eucharist those organs, one hopes, are not needed. If those organs are not needed, is simply ‘looking like’ a man enough? If not—if outward ‘perception’ and ‘resemblance’ (II’s terms) is insufficient—why?

Telos 3, at first glance, could sound like a version of the view within science and religion studies called NOMA (non-overlapping magisteria). According to this view, the fields of science and religion should never conflict because they study different things; i.e. science studies facts or the empirical world, religion studies value or the metaphysical world. If there is, as posited by Telos 3, a concept like theological sex, separate from biological sex, that would indeed solve one set of problems: the Church could simply say, ‘Theological maleness, which is a metaphysical category, is required for ordination. Who cares if biologists, using their empirical categories, disagree?’ It could be that some Christians believe this, but Catholic theology could not go in this direction.

However, there is another interpretation of Telos 3 that does not resort to NOMA, which John Paul II (in fact, Wojtyla) explains at one point as follows:

the expressions ‘the order of nature’ and ‘the order of biology’ must not be confused or regarded as identical, the ‘biological order’ does indeed mean the same as the order of nature but only in so far as this is accessible to methods of empirical and descriptive natural science, and not as a specific order of existence… (Wojtyla 1993, 57)

What he means here is that not all of reality is empirically accessible. The part that is accessible, we should not doubt, but don’t think that’s the whole story. This is far more promising than NOMA but notice that this still leaves the bishop without guidance. If the ordaining bishop cannot determine sex using the tools of biology, what tools should he use?

4. Conclusion

Recall my working hypothesis: Recent findings in biology suggest that the ‘only ordain men’ rule, thus stated, cannot be applied with certainty (as the Church says is required) to any candidate for ordination. I now see that my hypothesis wasn’t confirmed, or at least it was overstated.

Assuming we aren’t speaking of logical certainty, a bishop could be as ‘certain’ as anyone ever is in complex scientific findings. The Church says that they trust the ‘order of biology’ and what biologists today say about the chromosomal roots of sexual differentiation. Assuming today’s biology and genetics are right on the facts, a bishop could justly say that he was ‘certain’ that a given ordinand was male, provided he checked all the sex markers so far known to biology and all markers ticked the box indicating Male. It isn’t logically certain, but it’s as close as anything empirical is ever likely to be.

However, there is a problem with this scenario. The sex markers known to biology do not dispose themselves to box ticking. In fact, every single one of the markers has a spectrum of normal values; none of them are binary. In the case of secondary characteristics, like vocal register, that is obvious, but even chromosomes and genitalia aren’t binary markers. The SRY gene, normally found on the Y chromosome, sometimes gets pasted on the X. Sometimes different cells within the same person have different chromosomal patterns, a phenomenon called mosaicism. Developmentally, all humans start out with the rudiments of a clitoris in utero, which transforms into a penis in typical males before birth. Physicians need a spectrum to describe this transformation process; they cannot always tick a box.

These facts point to the importance of identifying the reason behind the rule; I mean, its telos. Without knowing the goal of the practice, we cannot decide complex cases. As an example, Aquinas thought that one impediment to a lawful ordination was being of illegitimate birth. So, he specifies the relevant telos behind this rule in order to make it applicable in tricky cases: being of good repute. That way the bishop would be able to weigh what to do in any particular case. So also with the impediment of deformity (Thomas’s telos here is personal comeliness), the impediment of murder (peacefulness), the impediment of slavery (freedom), and the impediment of childishness (reason). Without saying more about the telos of sex segregated ordination, we cannot decide complex cases.

Even though my hypothesis was not confirmed, a more modest version could be confirmed with further study, perhaps. Recent findings in biology suggest that the Church lacks a clear telos that could make sense of sex segregated ordination. Such studies that could clarify this telos are urgently needed, not least by the Church’s obligation to deal justly with intersex persons who have already been ordained and those intersex persons who sense a call to the ministerial priesthood.

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Cite this article

Perry, John. 2021. “Can Intersex Persons be Ordained as Catholic Priests?” Theological Puzzles (Issue 2).

Contact the author

John Perry
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