“Behold, I was brought forth in iniquity, and in sin did my mother conceive me. Behold, you delight in truth in the inward being, and you teach me wisdom in the secret heart.”-Psalm 51:5-6
Our external sins are an expression of our internal condition. God has made humans with the tendency to sexualize their feelings. Intercourse, at its purest form, is the love of a husband and wife sexualized. The love and commitment they have in their hearts towards one another was designed by God to be expressed physically through the joining of one flesh.