Saul had always been a religious man. It didn't do him much good. In the end he admitted it. His religion had been a disaster, just a cloak for a lot of foolishness and disobedience. Slavery, not freedom.
He then met God for real. It was a new birth. He was still Saul but he was changed. So changed that a change of name seemed appropriate.
He discovered the kindness and love of God. His life became productive. He tuned into God's generosity and gave it away to others.
The people of Crete had come from a very different background but they had the same needs, so Paul decided to stress some things.
1. It was in Jesus that he discovered who God really was.
2. The Holy Spirit had changed him, so much so he calls the experience a rebirth.
3. He was now in a right relationship with God, in a way he never was before.
4. He now wants to live the new life God has given him, and to get others to do so.
The key to it all is that God has in Jesus revealed his love and kindness. The truth, then, leads to real godliness, not the fake sort that Saul used to practice.
Jesus is the source of real productivity. We are not all like the old Saul but there is still one person like no other in whom God has shown his love and kindness. He is the one to follow.