John, who wrote this Gospel, was that disciple whom Jesus loved, who leaned on our Saviour's breast at supper, and inquired who should betray Christ; of whom Peter spake, 1 Thessalonians 21:21, and who testifieth these things, both concerning Peter, and concerning himself, and the church: the ancient church knew his testimony was true.
Related Commentaries of John 21:24
John 21:24
24 This is the disciple which testifieth of these things, and wrote these things: and we know that his testimony is true.