What Matthew and Mark call after a little while, Luke explains by saying, about the space of one hour after; but with regard to the space of time, John says nothing. Likewise when Matthew and Mark record not in the singular but in the plural number those who conversed with Peter, while Luke and John speak of one, we may easily suppose either that Matthew and Mark used the plural for the singular by a common form of speech, or that one person in particular addressed Peter, as being the one who had seen him, and that others trusting to his credit joined in pressing him. But now as to the words which Matthew asserts were said to Peter himself, Truly thou art one of them, for thy speech bewrayeth thee; as also those which to the same Peter John declared to have been said, Did not I see thee in the garden? whereas Mark and Luke state that they spoke to one another concerning Peter; we either believe that they held the right opinion who say that they were really addressed to Peter; (for what was said concerning him in his presence amounts to the same as if it had been said to him;) or that they were said in both ways, and that some of the Evangelists related them one way, some the other.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: de Con. Ev. ut sup.