Chapter 42 — Part IV: Prayer — Amen
Section 2. Necessity Of Explaining The Conclusion Of The Lord's Prayer — St. Jerome in his commentary on St. Matthew rightly calls this word what it really is, the seal of the Lord's Prayer. As then we have already admonished the faithful with regard to the preparation to be made before this holy prayer, so we deem it necessary that they should also know why we close our prayers with this word, and what it signifies; for devotion in concluding our prayers is not less important than attention in beginning them.