We also attribute it to insecurities, but in reality what betrays us is the excessive esteem we have of ourselves. Greatness and flattery fill us! For that reason, so you can not become a servant of God; Well, what you want is to be a master! and not servants!
"And so that the greatness of the revelations would not exalt me excessively, I was given a sting in my flesh ..." (2 Corinthians 12: 7).
When the successes are seen, then they can applaud us! Therefore, if you know the story of people who achieved great things, you will see that they had stingers, or were very tortured by their mind, or by problems in their family or had persecutions; things that would not allow him to be puffed up in their hearts.
Our Paul had great revelations! From Jesus himself came the call of an apostle: "Paul, called to be an apostle of Jesus Christ by the will of God ..." (1 Corinthians 1: 1) So the one who represented the beloved Jesus needed a thorn deep inside him that would He would sink every time he went to show off everything he knew. Because knowledge can bring us vanity, for that reason we need the thorn (the sting). Pablo only had to pray and pray, and pray again and again to be taken away, but he had no answer for what he asked for; that had to happen! "... concerning which three times I have prayed to the Lord, to take it away from me ..."). He wanted that thorn to be taken away from him. Paul saw it as an obstacle to the effectiveness of his apostolic labors. But, the spine was not removed (the sting) but God told him: "With my grace is enough for you, because my power is perfect in your weakness."
Although we are stunned, lost in thought, the power will flow, it will flow from God when necessary.