Barnabas wanted to bring John Mark; Paul did not - Acts 15:37-38
Edison tried several thousand time before creating the light bulb.
Reguarding failure as opportunity for growth encourages you to keeping going
John Mark returned home during the last trip because of possibly because he was frightened, discouraged, or homesick - Acts 13:13
Barnabas wanted to give him another chance; Paul disagreed and brought along Silas
John Mark matured and eventually Paul recongnized him as a effective minister of the gospel - 2 Timothy 4:11
Do you believe your past failures disqualify you from effective service in the church?