This thesis provides a theological reading of Judith Butler's gender theory. In dialogue with ancient and modern writers, theologians, and philosophers, I argue that Butler's gender theory is a protological theory. Butler enters the originary scene to recreate the human so that gender and sex can be perpetually reconceived in ways that reflect mundane desire. I argue that Butler's gender theory is therefore susceptible to the theological criticisms of coveting and idolatry. However, the methodological decision to structure the engagement with Butler as a dialogue does not permit unilateral criticism. The criticism levelled at Butler's thought is reversed to query a traditional theology of gender. The critique and countercritique reveal two laws in operation that result in death in life: (1) the law of desire and (2) the law of Adam and Eve. Drawing on the Apostle Paul's New Testament letter to the Romans, I offer an alternative—the law of God—that does not jettison desire or the originary creation of humanity. The ethical implications of this thesis emerge from reflecting theologically upon these three laws. I conclude by developing a chastened Christian ethics of gender that relies on a fresh understanding of gender as man-and-woman in the world, which considers human existence as good regardless of its location (pre- or post-lapsarian), while at the same time recognising that human existence is troubled by the fall. This protological grounding of man-and-woman in the world enables the theological concept of the imago Dei to be explored in relation to Christ's redemptive work, rather than the generally accepted originary terms that frame what is right or wrong gendered existence. Butler's desire of desire is not repudiated, but acknowledged theologically as fundamental to humanity's God-given vocation: one desires God's desire, which is to desire righteousness or the originary human vocation to image Jesus Christ. A Christian ethics of gender is therefore chastened as gender is reconceived theologically as a vocation of becoming like Christ—discipleship. Those who hear and are claimed by the originary divine performative utterance that man-and-woman in the world is very good are called to receive their embodied existence as (created) good, yet troubled (by the fall), yet with the hope of one's final embodied glorification in Christ.