Augustine of Hippo
Catena Aurea · Markusevangelium 14
And as Peter was beneath in the palace, there cometh one of the maids of the High Priest: And when she saw Peter warming himself, she looked upon him, and said, And thou also wast with Jesus of Nazareth. But he denied, saying, I know not, neither understand I what thou sayest. And he went out into the porch; and the cock crew. And a maid saw him again, and began to say to them that stood by, This is one of them. And he denied it again. And a little after, they that stood by said again to Peter, Surely thou art one of them: for thou art a Galilæan, and thy speech agreeth thereto. But he began to curse and to swear, saying, I know not this man of whom ye speak. And the second time the cock crew. And Peter called to mind the word that Jesus said unto him, Before the cock crow twice, thou shalt deny me thrice. And when he thought thereon, he wept.
(ubi sup.)y 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.