Then will I teach transgressors thy ways - As an expression of gratitude, and as the result of his own painful experience. He would show them, from that experience, the evil and the bitterness of sin in itself; he would show them with what dreadful consequences sin must always be followed; he would show them the nature of true repentance; he would show them what was required in order that sin might be forgiven; he would encourage them to come to that God who had forgiven him. So the Saviour charged Peter, from his own bitter experience in having fallen under the power of temptation, to strengthen and encourage those who were struggling with the depravity of their own hearts, and who were in danger of falling: “And when thou art converted, strengthen thy brethren,” Luke 22:32.
And sinners shall be converted unto thee - They would see from his case the evil of transgression; they would learn from his example that mercy might be found; they would be persuaded to flee from the wrath to come. The best preparation for success in winning souls to God, and turning them from the error of their ways, is a deep personal experience of the guilt and the danger of sin, and of the great mercy of God in its forgiveness. No man can hope to be successful who has not experienced this in his own soul; no one who has, will labor wholly in vain in such a work.