ISB ~ John 18 v27

again denied it:Three times Peter denies his association with Jesus (18:17, 25), just as three times he fell asleep while Jesus prayed in agony (Mk 14:32-42) and three times he will renew his commitment to Jesus after the Resurrection (Jn 21:15-17).

the cock crowed:Possibly the Roman bugle call that signaled the end of the “cockcrow” at about 3 A.M.See note on Mk 13:35.