But that ye also may know my affairs, and how I do, Tychicus, a beloved brother and faithful minister in the Lord, shall make known to you all things:
Ver. 21. But that ye may know] It is of good use to the Church to know the lives and affairs of men eminent in goodness and of exemplary holiness, that others may express them; as Polycarp did John the Evangelist, as Irenaeus did Polycarp, as Cyprian did Tertullian, Paraeus did Ursin, &c.