Why did God give Paul a thorn in the flesh?
God gave Paul a thorn in the flesh, a messenger of Satan, to buffet him and keep him humble. Because of the abundance of revelations given to him, this suffering prevented Paul from becoming proud or being exalted above measure.
Les explains that God put a human suffering on Paul's body to keep him humble, lest he should get proud and feel exalted. The thorn was a messenger of Satan to buffet him, and it related to the abundance of revelations Paul had received. Paul did not want anyone to think of him above what they saw or heard, and he had nothing in the flesh to brag about.