Psalms 51:13

Then I will teach transgressors your ways,

so that sinners will turn back to you.

(v13, NIV)

Why is it not until "then" that David will teach transgressors God's ways? Why is the teaching of God's ways dependent on other things? David seems to need a pure heart, joy of God's salvation and a willing spirit in order to teach the ways of God. Perhaps it is because David needs to be clean himself before he can teach those who are unclean. If I were a well known thief who continued in that, how could I convince other thieves to stop stealing? I would be a hypocrite if I did that. Instead, I would need to turn from my ways before I could even reach out to them in that manner. David first needs to be clean before he can begin to teach others. In the same way, we need to begin in our cleansing process. We can't tell others about God when our lives look no different than theirs. Sure, we are all sinners and we all fall short. Even as a follower of Jesus Christ we will continue to fall short of his glory. But there needs to be a cleansing or a progression of some sort. Teach others and tell others about his ways.