fell, therefore, through over self-confidence, and by neglecting our Lord’s exhortation: “Watch and pray, that ye enter not into temptation!”
Peter's fall should be a warning to us, to carefully avoid bad companions, and the occasions of sin; to remember our weakness and instability; and not to trust too much in ourselves, but to ask humbly for the assistance of grace. It was not without reason that our Lord taught us to pray: “Lead us not into temptation!” St. Paul says (i Cor. 10, 12): “He that thinketh himself to stand, let him take heed lest he fall!”
The conversion of Peter was the work of the preventing grace of our Lord Jesus Christ. The cock crew immediately after his first denial; and this was intended to remind him of his Lord’s warning words, and of his own promise to lay down his life for Him. However, he paid no heed to this first cock-crow, and fell deeper into sin; for an outward warning is of no avail without the inward voice of grace. Even the second cock-crow would not have moved him in his distraction, had not our Lord at the same moment cast his gracious glance on the fallen apostle. With that one look which met his eye, grace penetrated the soul of the unfaithful apostle, and gave him light to see how low he had fallen, and how grievously he had sinned. His heart and will were moved, he detested his sin, and bitterly repented of it. Peter corresponded with the helping grace which was given to him; he opened his heart to it, obeyed its promptings, and was therefore converted. To Judas also great grace was given, in the Garden of Gethsemani, but he resisted it, and therefore perished in his sins.
The repentance of Peter was both real and supernatural. So great was his grief of soul for the sin which he had committed, that bitter tears of contrition flowed from his eyes. His contrition was also supernatural, and was indeed a perfect contrition, for he was sorry purely because he had offended his beloved Lord, and because he had increased His sufferings; for of all our Lord’s sufferings the one that pained Him most was that Peter, His highly-favoured and chosen apostle, should be ashamed of Him and deny Him in such a cowardly manner. Peter repented of his fall from perfect love for his Divine Master, whose countless benefits and graces he had repaid with such base ingratitude. Let us, too, if we fall into mortal sin, do penance at once, as Peter did, and awaken a perfect contrition in our hearts. His repentance, furthermore, was no passing one: his sorrow for his sin oppressed him all his life, and it is said that each time he heard a cock crow he was moved to a sense of contrition for his sin, and that his eyes were always red with weeping. All his life long he worked mightily for the glory of his Master and the salvation of souls, and unceasingly preached the Gospel, till at last he gave up his life for Jesus. Great was his fall, but still greater was his penance: and he has by his contrition and life-long satisfaction become the model of a true penitent.
