I used to think that I had made too many mistakes to be used by God. I have done a lot of terrible things in my life; things that hurt me and the ones I love. Though I knew God had forgiven me, I believed that my past disqualified me to be effective in God's Kingdom.
How could God use a messed up, selfish, sinful person like me? I wanted my life to glorify God, but my past haunted me. How could I talk to people about Jesus? Wouldn't I embarrass Him?
When I was praying one day I read a scripture that really touched my heart. "In him we were also chosen, having been predestined according to the plan of him who works out everything in conformity with the purpose of his will..." (Ephesians 1:11). What that meant to me was that God can and will work everything out in my life to glorify Him... my triumphs as well as my failures.
What a relief to know that when I mess up, God can still use me. In fact, He only uses flawed people. Because we are all flawed. But He loves us and will use every single aspect of our lives that we turn over to Him.