Of the many difficult formulations in Karl Barth's ‘Special Ethics’, none seems less amenable to acceptable interpretation than his conception of the relation of male and female. I do not refer to Barth's insistence that Man, created as male and female, maintain both the unity and distinction required for true co-humanity. I refer, rather, to his puzzling (even if textually supported) assertion that this co-humanity is ordered by God in such a way that the woman is ‘sub-ordinate’ to the man without inferiority or disadvantage. Putting aside the exegetical issues involved, I will try to show that Barth's redefinition of the concept of sub-ordination gains coherence when understood as an ‘ordering’ of human life by a revealed order of creation, which in turn is an expression of the divine life itself. I will argue that the analogy Barth draws between the order of the Trinity and sexual relationship is authorized by his doctrine of creation, by his view of Christ as the analogia relationis, and by what I believe to be his application of the doctrine of perichoresis to anthropology. And finally, I want to suggest that, while some of Barth's language may have to be set aside, the arguments described here inform the presuppositions and method of an ethic more relevant for moral discrimination than has commonly been supposed.