John Chrysostom

(Hom. lxxxiii. 2) But how could he, who had been forbidden ever to strike on the cheek, be a murderer? Because what he had been forbidden to do was to avenge himself, but here he was not avenging himself, but his Master. They were not however yet perfect: afterwards ye shall see Peter beaten with stripes, and bearing it humbly. And cut off his right ear: this seems to shew the impetuosity of the Apostle; that he struck at the head itself.