2 Corinthians 12:7-10 (ESV)
7 So to keep me from becoming conceited because of the surpassing greatness of the revelations,[a] a thorn was given me in the flesh, a messenger of Satan to harass me, to keep me from becoming conceited. 8 Three times I pleaded with the Lord about this, that it should leave me. 9 But he said to me, “My grace is sufficient for you, for my power is made perfect in weakness.” Therefore I will boast all the more gladly of my weaknesses, so that the power of Christ may rest upon me.10 For the sake of Christ, then, I am content with weaknesses, insults, hardships, persecutions, and calamities. For when I am weak, then I am strong.