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National Marriage Week: Sexual difference and "dual unity"

This is the fifth post in our series about sexual difference.

Earlier posts:

Sexual Difference & “Dual Unity”

In this post, we’ll look at a second helpful way of understanding sexual difference, one that is found in Pope John Paul II’s teachings on the theology of the body, where the Holy Father speaks of “double unity” or “dual unity.” Reflecting on the creation narratives of Genesis, John Paul II writes,

“We observed that the ‘definitive’ creation of man consists in the creation of the unity of two beings. Their unity denotes above all the identity of human nature; duality, on the other hand, shows what, on the basis of this identity, constitutes the masculinity and femininity of created man” (TOB, sec. 9.1, emphasis original).

“Unity,” then, refers to the common humanity and dignity that both men and women have – one humanity, participated in by both. In Eve, Adam finds another creature who, like himself, finds no “suitable partner” among the animals (Gen 2:20). He finds another creature created “in the image of God” (Gen 1:27). And so, as John Paul II writes, “Joy for the other human being, for the second ‘I,’ dominates in the words the man (male) speaks on seeing the woman (female)” (TOB, sec. 8.4).

Yet although man and woman are united in a common humanity, they are irreducibly different. As John Paul II puts it, “Man, whom God created ‘male and female,’ bears the divine image impressed in the body ‘from the beginning’; man and woman constitute, so to speak, two diverse ways of ‘being a body’ that are proper to human nature in the unity of this image” (TOB, sec. 13.2). The “duality” of human nature is precisely the sexual difference, masculinity and femininity.

For John Paul II, the “unity in the flesh” that takes place in the sexual encounter between man and woman has its foundation in their “unity in humanity”:

“When they unite with each other (in the conjugal act) so closely so as to become ‘one flesh,’ man and woman rediscover every time and in a special way the mystery of creation, thus returning to the union in humanity (‘flesh from my flesh and bone from my bones’) that allows them to recognize each other reciprocally and to call each other by name, as they did the first time” (TOB, sec. 10.2).

It is only because of man and woman’s unity-in-difference (two sexes within a shared humanity) that they are able to come together in the fruitful union of marriage. Without a shared humanity, this encounter would not be personal; and without being different sexes, this union “in the flesh” could not take place at all. For Pope John Paul II, the sexual difference is fundamentally “a reciprocal ‘for’ that can and must…serve the building of the unity ‘of communion’ in their reciprocal relations” (TOB, 41.4).

Next: Why Does Sexual Difference Matter?

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