A.T. Robertson Commentary 2 Corinthians 12:5

"On behalf of such a one will I glory: but on mine own behalf I will not glory, save in [my] weaknesses." — 2 Corinthians 12:5 (ASV)

But on mine own behalf (υπερ δε εμαυτου). As if there were two Pauls. In a sense there were. He will only glory in the things mentioned above, the things of his weaknesses (11:30).