Mark 14:30 and 72 record that the cock crowed twice during Peter's denials, whereas Matthew 26:34, Luke 22:34, and John 13:38 state it would not crow until Peter had denied Jesus thrice. Traditional harmonization explains that the other gospels omit the first crow as details irrelevant to the core prediction, or that 'cockcrow' refers to a general dawn timeframe; conversely, critical scholarship views it as a distinct redactional variation unique to Mark's tradition.