[After Peter's second denial of Jesus,] one of the household slaves of the high priest, a relative of the man whose ear Peter had cut off, asked, "Didn't I see you out there in the olive grove with Jesus?" Again Peter denied it. And immediately a rooster crowed.
— John 18:26-27 NLT
Three strikes and you're out. That's true in baseball. That's also true under some of the laws in the United States. It is not true with God's grace. Regardless of what you've done or how many times you've done it, you are not too broken to be restored. Jesus will confront Peter about his three-fold failure. However, each time Jesus will affirm his value and call him back to useful service.  Sin — failure at our most important commitment, our commitment to God — is horrible. It brings all sorts of problems into our lives. However, sin does not have the final word in our lives: God's grace does. Jesus died for sinners — for you and for me! Our sin does not disqualify us from being used by God if we will repent and let holy God remake us into someone fit to serve! So don't give up if you have struck out repeatedly in your walk of faith. Jesus reclaimed Peter, and he can reclaim you!
Holy God and Father, please don't let my sin steal my faith away from your transforming power and grace. I believe that you can remake me and empower me beyond my failures and my moments of unfaithfulness. Grow me and mature me so that those moments occur less and less frequently. Raise me up to be your loyal, useful, righteous, and faithful servant. In Jesus' name, I pray. Amen.