There is a clear assumption in many passages in the Qur'an that marriage is between men and women. Passages that talk about how a couple should decide when to wean a child, what times of day it is permissible to have sexual relations during Ramadan, or what to do when conflict arises and a divorce seems the best solution.

But other passages -- passages that talk about the fundamental nature of human relationships as a duality -- do not have a gender dichotomy. The word "zauj," often translated as mate or spouse, signifies one half of a partnership, both husband and wife. This is a powerful concept which affirms the fundamental equality of both spouses and leaves room for a genderless conception of human partnering....