Psalm 1 teaches us that the man who walks in the way of the Lord is blessed. In the 25th psalm, David is praying for just that. Trusting in the goodness of the Lord and praying for mercy and grace, David asks the Lord to teach him. I doubt he means that he doesn’t know what’s right. Rather, he is asking God to help him do what is right.
There is a big difference between knowing how something works and being able to do it. On the one hand I know how to play a piano: you hit the keys and move the pedals, and little hammers hit strings and noise is produced. Yet I have no idea how to make beautiful songs come from the piano. David knows what’s right, but his sinful nature keeps him from walking in it. This is the same struggle Paul wrestled with when he said, “For what I want to do I do not do, but what I hate I do” (Romans 7:15). Certainly it is our struggle as well.
Lift up this prayer of supplication: “Lord, let your Holy Spirit guide us and correct us. Teach us your ways and teach us to walk in them.”