John 8:57 - Ellicott's Commentary On The Whole Bible

Thou art not yet fifty years old. — There is no reason to doubt that we have the correct reading here, though some, from Chrysostom downward, have sought to avoid what seemed to them a difficulty, by substituting “forty” for “fifty.” Others, and among them were the “Elders who in Asia conferred with John, the Lord’s disciple,” have held that our Lord was between forty and fifty years of age at the time of his public ministry. We know this from the testimony of Irenaeus, who appears to have this very passage in his mind, for he says, “As the gospel and all the Elders witness” (Lib. 2 chap. 22 § 5; Oxford Translation, p. 160). But “fifty years” was the period of full manhood (Numbers 4:3; Numbers 4:39; Numbers 8:24). This is expressed in round numbers, and there is no care to be more exact in comparison with the two thousand years which had passed since the close of Abraham’s earthly life. The thought is, “Thou art still a young man, and hast thou seen Abraham who died twenty centuries ago?”