21 The salutation of me Paul with mine own hand.
[AD 384] Ambrosiaster on 1 Corinthians 16:21
Paul makes it clear that he has written the subscript with his own hand.

[AD 398] Didymus the Blind on 1 Corinthians 16:21
To avoid any suspicion of forgery, Paul signs the letter with his own hand.

[AD 407] John Chrysostom on 1 Corinthians 16:21
"The salutation of me Paul with my own hand;" intimates that the Epistle was composed with great seriousness; and therefore he added,