Irenaeus Against Heresies Book IV And, "It hath been said, Thou shalt not forswear thyself. But I say unto you, Swear not at all; but let your conversation be, Yea, yea, and Nay, nay."[154] Constitutions of the Holy Apostles Book VI He who made a law for swearing rightly, and forbade perjury, has now charged us not to swear at all.[146]