Mt 26:73-75
A little later the bystanders came over and said to Peter, “Surely you too are one of them; even your speech gives you away.” At that he began to curse and to swear, “I do not know the man.” And immediately a cock crowed. Then Peter remembered the word that Jesus had spoken: “Before the cock crows you will deny me three times.” He went out and began to weep bitterly.