1 Corinthians 16:21

The salutation of me, Paul, with mine own hand - It is evident that Paul was accustomed to employ an amanuensis (copyist) in penning his epistles (see the note on Romans 16:22), though he signed his own name, and expressed his Christian salutation in every epistle, 2 Thessalonians 3:17; compare Colossians 4:18. This gave a sanction to what was written; was a proof that it was his own, and was a valuable token of affectionate regard. It was a proof that there was no fraud or imposition. Why he employed an amanuensis is not known.