2 Corinthians 12:6-7

For if I shall desire to boast, I shall not be a fool; for I will say the truth; but I forbear, lest any one should think as to me above what he sees me to be, or whatever he may hear of me. And that I might not be exalted by the exceeding greatness of the revelations, there was given to me a thorn for the flesh, a messenger of Satan that he might buffet me, that I might not be exalted.