Paul regularly followed the ancient custom of dictating his letter to a secretary and writing only the last greetings with his own hand (see, e.g., Romans 16:22; Galatians 6:11; Colossians 4:18). The last words, written in the sender’s own hand, served to confirm the genuineness of the letter. When it came to the apostles’ letters, such a confirmation was of vital importance (see 2 Thessalonians 2:2; 2 Thessalonians 3:17).
21 Je vous salue, moi Paul, de ma propre main.