The hard-charging young Pharisee was on the way to Damascus to do the Lord's work. Saul of Tarsus thought that achieving divine favor was within his grasp. Then, he met the Lord Jesus on the road. A rebuke from divine authority when a person thinks he or she is firmly in the right shakes the very core of a life's creed. Paul had to stop and rewrite his, and God gave him the letter to the Romans that we study to this day.
We think of many things when Paul discusses his 'thorn' that he asked God to remove three times. It may well be that nothing physically was wrong with the apostle. The thorn may refer to the former Pharisee's strong desire to prove himself good enough to God. We face that same challenge these many years later. We read of God's grace, but we try to set it aside to prove that we don't need it by becoming good enough to merit God's favor. With good and godly reason God told Paul that His grace is sufficient. We too must come to realize that God's grace through faith in Christ Jesus is our only and best hope.
A perfected mind, or body, or house, or job, or anything else in this life that might somehow meet our weak and flawed standard of perfection might only serve to anchor us to a doomed world. Better by far to meet God's standard given by grace through what our Lord Jesus accomplished than to try to go it alone and fall on those thorns. Rejoice in the day the Lord has given!Bucky