Puritan Board Junior
When I began going to the OPC congregation I am now a member of the pastor, praying at the pulpit on Sunday morning, included, "Forgive us for those sins we are aware of, and those we are not aware of." I had never thought of that possibility and commented on it to him after the service. He said, "That is from Psalm 19."I'd start with Psalm 19:12.
Reading James 4:17 brings to my mind
40 And he came to the disciples and found them sleeping. And he said to Peter, “So, could you not watch with me one hour? 41 Watch and pray that you may not enter into temptation. The spirit indeed is willing, but the flesh is weak.”
and John 2:24-25
24 But Jesus on his part did not entrust himself to them, because he knew all people 25 and needed no one to bear witness about man, for he himself knew what was in man.