Few teachings are more incomprehensible to the modern secular person than traditional Christian teaching on sex. The heart of Paul’s argument is that Christians have been “bought” with the blood of Jesus, therefore everything we do with our lives, including our bodies, should be aligned with his purposes. In fact, the  bond created by human sexual intimacy is actually a shadow of the ultimate intimacy of being united to God by faith. This teaching stands in direct contradiction to the secular creed of absolute individual sovereignty. Yet while it flows from the Gospel of salvation by grace, it is still secondary to it. When we make secondary matters primary, we undermine both.