2 Corinthians 5:17-21 (New International Version)
17Therefore, if anyone is in Christ, he is a new creation; the old has gone, the new has come! 18All this is from God, who reconciled us to himself through Christ and gave us the ministry of reconciliation: 19that God was reconciling the world to himself in Christ, not counting men's sins against them. And he has committed to us the message of reconciliation. 20We are therefore Christ's ambassadors, as though God were making his appeal through us. We implore you on Christ's behalf: Be reconciled to God. 21God made him who had no sin to be sin for us, so that in him we might become the righteousness of God.
This is one of my favourite passage in the bible. I love the imagery of becoming totally new, that God cleans us up and gives us a new heart and a new Spirit. It's nothing we can do, it is God who makes us a new and cleans us up!
I think it's incredible that Jesus didnt do it all himself in relation to spreading the news, but he gave us the responsibility to tell others about him.
Just as our country has ambassadors around the world representing us to other nations. God has made us ambassadors for him to those who don't know him.
Next time you feel shame, regret or guilt from the past, remember the God has made you a new creation - THE OLD IS GONE! THE NEW HAS COME