The churches have forgotten that, until the 17th century, the dominant understanding of sex and gender was of a single humanity, ‘man’, within which women were imperfect, malformed men. Later, a two-sex view of humanity, supposedly established by modern science, became preferred. The idea of the complementarity (not equality) of the sexes arose directly from this view. The Christian Gospel offers neither an ancient one-sex theory, nor a modern two-sex theory, but a single inclusive humanity, made by God and redeemed by Christ, in which differences of all kinds are a means towards communion instead of conflict.
From a paper called Redeeming Gender, by Prof Adrian Thatcher.