John Mark
Mark 14:66BSB·traditional attribution

While Peter was in the courtyard below, one of the servant girls of the high priest came down

Matthew Henry Presbyterian @wholebiblehenry

We have here the story of Peter's denying Christ. 1. It began in keeping at a distance from him. Peter had followed afar off (Mar 14:54), and now was beneath in the palace, at the lower end of the hall.

Commenting on Mark 14:66-72

John Gill Reformed Baptist @doctorgill

And he denied it again,.... That he was one of the disciples of Jesus: and a little after; about an hour after, Luk 22:59; they that stood by, said again to Peter, surely thou art one of them; one confidently affirmed that he was with Jesus, and another challenged him with seeing him in the garden with him, Luk 22:59, and in general they were...

William Burkitt Anglican @expositoryburkitt

This last paragraph of the chapter gives us an account of the fall and rising of Peter; of his sin in denying Christ, and of his recovery by repentance. Both are considered distinctly in the notes of Matt 26:69. that which is here farther to be taken notice of, is as followeth. Observe, 1.