A few thoughts on purity culture
Now that the man who wrote "I kissed dating goodbye" and jump-started the "purity culture" movement in Christianity has become an apostate, it has become fashionable for Christians to bash purity culture as legalistic and oppressive, and even as heretical. Any good thing can be twisted, of course, but there are many good things about purity culture and Christians are fools to toss it aside.
Obviously God expects sexual purity. Chapter 6 of the Apostle Paul's first epistle to the Corinthians tells us to "flee fornication" and the New Testament is filled with exhortations to keep ourselves sexually pure. We are to save the sex act for the lifelong, monogamous union of one man and one woman. We must continue to submit to this commandment while we also avoid legalism and self-righteousness.
One of the errors common in purity culture is that once someone sins sexually, that sin will define you. Obviously that is not true. The blood of Christ washes away our sin, and we are free from it. But the reality is that sin does have lasting consequences, and the Apostle Paul does warn that those who sin sexually are sinning against their own bodies. The medical evidence of this is the spread of fatal sexually transmitted diseases.
But what purity culture got wrong is that taking a pledge or following a specific system is no substitute for a lack of good teaching and discipleship. If anything, signing a purity pledge may make one more vulnerable to sexual sin, because Satan loves nothing more than turning Christians into hypocrites. This is why the fight against sin is a lifelong war, not a single battle that can be won and forgotten. Our justification through the blood of Jesus Christ means sin will not condemn us, but sanctification does not end until we are dead.