God’s design was one man with one woman for life as the ideal expression of both the image of God, as well as sexual fulfillment for a man and a woman. So what should that expression of sexuality look like in the context of a marriage? God intended for the sexual fulfillment of a spouse to rest squarely on the shoulders of the other spouse, meaning our sexual desires are not ours to fulfill; they are our spouse’s responsibility. Our spouse’s desires are not theirs to fulfill by themselves, but ours to fulfill for them. Paul goes as far as to call it a duty or an obligation to our spouses, because sex between a married couple creates a connection between them that they don’t have with anyone else, and that connection glorifies God as each spouse serves the other.