Evidence that Irenaeus's Against Heresies Was Rewritten (Perhaps Many Times) After His Death

There is a critical section of Book Four (AH 4.6.1) where Irenaeus not only thinks the Gospel of Mark contained the saying - “No man knoweth the Son, but the Father; neither knoweth any man the Father, save the Son, and he to whom the Son has willed to reveal [Him]" - now confined to only Matthew and Luke. As Harvey notes there is a point a little later where Irenaeus actually cites with apparent approval the saying in the form know to have existed among the heresies - “No man knoweth the Son, but the Father; nor the Father, save the Son, and those to whomsoever the Son shall reveal [Him].” Harvey observes here, that “it is remarkable that this text, having been correctly quoted a short time previously in accordance with the received Greek text, ᾧ ἐὰν βούλητας ὁ υἱὸς ἀποκαλύψαι, the translator now not only uses the single verb revelaverit, but says pointedly that it was so written by the venerable author.” It is probable, therefore, that the previous passage has been made to harmonize with the received text by a later hand; with which, however, the Syriac form agrees.