Because of the surpassing greatness of the revelations, for this reason, to keep me from exalting myself, there was given me a thorn in the flesh, a messenger of Satan to torment me—to keep me from exalting myself! 2 Corinthians 12: 7
Three times, the great apostle Paul asked the Lord to remove a thorn that tormented him (2 Corinthians 12: 8). The question always asked when that is read is this, “What was the thorn?” The answer is “no one truly knows.” I’m sure that once in heaven, the apostle will be swamped by many wanting to know just what he meant.
In the meantime, we speculate. Pretty much all agree that Paul’s use of the word “thorn” was metaphoric, not literal. After that, the nature of it is pretty much up in the air. Paul’s torment has been variously described as being of a physical, emotional, or spiritual nature.
For a long time, my opinion has been that his affliction was extremely poor eyesight. After all, he was blinded on the road to Damascus. Subsequently he regained sight, but several scriptural passages indicated that it wasn’t a full recovery (Acts 23: 2-5; Galatians 4: 15; 6: 11).
Now I’m re-thinking it. What’s caused me to do so, after many more reads, is the emergence of Paul saying that the thorn was a messenger from Satan. The Bible, more times than not, describes spiritual messengers as angels from the Lord. One of the things we know about Satan is that he’s a counterfeiter. He likes to imitate things that God does. Therefore, Satan’s messenger is probably an angel too, albeit a fallen one.
If so, a fallen angel, like its master, would be in the business of temptation. This being the case, the angel would have constantly been trying to lure Paul into whatever weakness or vice his flesh was inclined to indulge in.
The Lord, as we know, refused to remove this torment from Paul. It was His way of keeping Paul humble, for he easily could have been filled with pride. After all, he was given exclusive looks into heaven, plus an abundance of inspiration to write for the New Testament. God, though, did give him more than enough grace to be strong in his weakness (2 Corinthians 12: 9).
So my two-cent conclusion on the matter is the following. Paul’s thorn was a tension between his flesh being tempted toward a particular sin (maybe even sins) and his desire to walk in the Spirit.