This article examines the “grey areas” of sexual consent in Belgian Catholic couples before the “sexual revolution”, based on family pastoral care manuals and on a corpus of letters exchanged between Catholic marriage counselors and readers of the Catholic magazine “Feuilles Familiales”. I show, on the one hand, how the emergence of a sexual ideal of “physical harmony” in the early 1950s led moralists to challenge the traditional notion of “marital duty” in favor of a valorization of the reciprocity of desire and pleasure between spouses. The analysis of couples’ letters shows, however, that this egalitarian conception proposed by moralists fails to take into account gender inequality in the negotiation of sexuality. The ideal of physical harmony turns out to be very gendered: used mainly by men to associate wives with their sexual pleasure, and by women to reformulate the difficulties of their couple. In a context where contraception is still banned, the sacrifice required to achieve physical harmony is unequally distributed according to gender. The analysis shows the integration by women of the role of moralization of sexuality, but also the multiple reasons that push Catholic women to accept or solicit sexual relations, among which desire or pleasure are far from being the only consideration. Therefore, if marital harmony certainly led many couples to attach more importance to their partner’s desire and pleasure, it was also a disruptive factor for other couples, especially when combined with the religious ban on contraception. By making desire and pleasure essential motives for female sexuality in the eyes of men, it indeed placed new pressure on Catholic couples, in particular on women. ; info:eu-repo/semantics/published