One Flesh

“One Flesh” is Screwtape’s name for the enduring relation he says sexual intercourse establishes, whether or not the partners feel affection or call themselves in love. His treatment makes the expression a hinge between bodily union, marriage, and the larger contrast between Hell’s competitive idea of selfhood and the Enemy’s account of love. At the same time, because the argument is delivered by a devil whose reliability the preface cautions readers not to take for granted, his explanation should be read as part of the book’s ironic presentation of infernal reasoning.

The expression and its meaning

Screwtape argues that the Enemy’s description of a married couple as “one flesh” is not limited to marriages that are happy or founded on the feeling of being in love. He invokes Paul’s broader application of the phrase: in Screwtape’s account, intercourse itself makes the participants “one flesh.” The phrase therefore describes a relation that does not depend on whether those involved welcome it or recognize its significance.

He distinguishes this lasting relation from the emotion commonly called being in love. That emotion may accompany a marriage, but it is not, in his account, what makes the union real or holy. Screwtape says that people can be led to treat the phrase as a poetic compliment for romantic excitement, when he presents it instead as a plain description of the significance of sexual intercourse.

Marriage, feeling, and the family

Screwtape situates the expression within a larger account of marriage. He says the Enemy’s demand for human sexuality takes the form of either abstinence or monogamy, and describes Hell’s effort to narrow marriage by teaching that being in love is its only respectable basis. The accompanying error is to suppose that marriage ought to preserve the initial excitement indefinitely, and that its obligation lapses when excitement fades.

Against this confusion, Screwtape describes fidelity, fertility, and goodwill as the purposes with which people may enter marriage in obedience to the Enemy’s design. Romantic feeling may precede such a marriage, but he presents it as a possible accompaniment, not its foundation. Treating a heightened version of the feeling as marriage’s necessary basis can discourage people who do not feel it from marrying, even when they seek a faithful partnership for mutual help, chastity, and the transmission of life. Conversely, infatuation can be called love and used to excuse a marriage without regard to the partner’s character or religious difference.

The phrase also belongs to Screwtape’s account of family life. He says that sexual desire is joined to affection between the partners and that children depend on their parents, who in turn receive an impulse to support them. The family thus becomes a form of unity in which its members remain distinct but are also joined by conscious responsibilities. In Screwtape’s hostile reading, these arrangements are further means by which the Enemy introduces love into human relations.

Infernal competition and the counter-logic of love

The claim that two people can become “one flesh” runs against the principle Screwtape identifies as Hell’s philosophy: one self is not another, each being’s good is separate, and one party’s gain entails another’s loss. He condenses this assumption in the claim that to exist is to compete. On that model, relation is ultimately a contest over space, will, and advantage.

Screwtape presents the Enemy’s alternative as a unity that does not erase distinction. He calls the idea that one self’s good can be another’s good a contradiction, yet his examples reveal what the contrast means: the Enemy’s pattern includes the unity of three persons in one God and the cooperation of parts in an organism. “One Flesh” belongs to this wider challenge to the assumption that beings can only preserve themselves by excluding or absorbing others.

The distinction also clarifies why Screwtape describes sexual union as consequential regardless of the partners’ feelings. He claims that the relation it creates must be either eternally enjoyed or eternally endured. From that asserted reality, people are liable to draw a mistaken conclusion: that the emotion of being in love is what creates the relation, and therefore the sole ground of a happy or holy marriage. The error confuses a feeling that may accompany a union with the significance Screwtape says the union already possesses.

Distortion through self-conscious sacrifice

Screwtape’s later advice about courtship and marriage shows how the idea of unity can be distorted in ordinary conduct. He recommends encouraging couples to mistake erotic excitement for charity and to make the mutual concessions that come naturally during infatuation into a permanent law for their married life. When the excitement fades, they may lack the charity needed to sustain that standard, while still believing that love should make sacrifice effortless.

This distortion can turn apparent generosity into a contest. Each partner argues for the other’s supposed wishes rather than stating their own; both may end by doing something neither wants, while privately claiming credit and resenting the other for accepting the sacrifice. In Screwtape’s example of a family deciding whether to have tea in the garden, one person signals reluctance while presenting willingness as unselfishness; the others withdraw the proposal for the same nominal reason, until insistence and resentment produce a quarrel. The episode shows how a language of unity can conceal competing claims rather than resolve them.

The book’s framing complicates Screwtape’s authority. Its preface warns that the devil is a liar and that even his account of human beings may be distorted by wishful thinking. Accordingly, his description of “One Flesh” is not simply a neutral theological statement: it is a devil’s explanation of a relation that his own competitive logic cannot comfortably accommodate. The expression’s significance emerges in that tension—union does not mean that distinct people are absorbed into one another, but neither can it be reduced to separate selves pursuing separate goods.