Colossians 4:9

Onesimus : a man who was the slave of Philemon

Colossians 4:12

Epaphras : a man who was a fellow laborer with Paul

Ephesians 6:21

Tychicus : a man who was a fellow worker with Paul

Philippians 2:25

Epaphroditus : a man who was a messenger between Paul and the churches