For Christians, especially postmodern Christians bereft of any consensus, sexual difference is a similar category. We will not know what it means until we allow God to tell us what it means. The tradition has claimed that we do not know who we are and what it means to find ourselves differentiated as men and women until we allow the premises and practices of revelation to unfold. In the tradition, stretching from Augustine to John Paul II, sexual difference is not mute, inert, nonexistent, or indifferent. In this tradition, God brings man to woman and tells the two sexes something they would not otherwise know: that their creation is good, that their creation as two sexes is for the sake of enabling a church and a covenant, and that, despite their fallenness, their twoness can in itself become a witness to reconciliation and redemption through marriage. Marriage gives this aspect of our creation the power to testify, and the nonmarried offer supporting testimony through their chastity, which creates the social ecology supporting marriage.