This however is almost certainly false, as the ancient Latin translation of Irenaeus has 'Christi autem generatio,' and it was extremely natural for a copyist to substitute the generally received text, especially in a combination of words that was so familiar.

Irenaeus leaves no doubt as to his own reading on the next occasion when he quotes the passage, as he does twice over.

Here he says expressly: 'Ceterum, potuerat dicere Matthaeus: _Jesu vero generatio sic erat_; sed praevidens Spiritus sanctus depravatores, et praemuniens contra fraudulentiam eorum, per Matthaeum ait: _Christi autem generatio sic erat_' [Endnote 330:2].

Irenaeus founds an argument upon this directed against the heretics who supposed that the Christus and Jesus were not identical, but that Jesus was the son of Mary, upon whom the aeon Christus afterwards descended.

In opposition to these Irenaeus maintains that the Christus and Jesus are one and the same person.
There is a division of opinion among modern critics as to which of the two readings is to be admitted into the text; Griesbach, Lachmann, Tischendorf (eighth edition), and Scrivener support the reading of the MSS.; Tregelles, Westcott and Hort, and M'Clellan prefer that of Irenaeus.