The other Evangelists do not mention this crowing of the cock; they do not however deny the fact, as also some pass over many other things in silence, which others relate.
There follows: “And a maid saw him again, and began to say to them that stood by, This is one of them.”
Augustine [ed. note: for a harmony of this portion of the Gospel, v. Williams on the Passion, p.101]: This maid is not the same, but another, as Matthew says. Indeed, we must also understand, that in this second denial he was addressed by two persons, that is, by the maid whom Matthew and Mark mention, and by another person, of whom Luke takes notice.
It goes on: “And he denied it again.”
Peter had now returned, for John says that he denied Him again standing at the fire; wherefore the maid said what has been mentioned above, not to him, that is, Peter, but to those who, when he went out, had remained, in such a way however that he heard it; wherefore coming back and standing again at the fire, he contradicted them, and denied their words. For it is evident, if we compare the accounts of all the Evangelists on this matter, that Peter did not the second time deny Him before the porch, but within the palace at the fire, whilst Matthew and Mark who mention his having gone out are silent, for the sake of brevity, as to his return.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).