Cock-crowing
    In our Lord's time the Jews had adopted the Greek and Roman
    division of the night into four watches, each consisting of
    three hours, the first beginning at six o'clock in the evening
    (Luke 12:38; Matt. 14:25; Mark 6:48). But the ancient division,
    known as the first and second cock-crowing, was still retained.
    The cock usually crows several times soon after midnight (this
    is the first crowing), and again at the dawn of day (and this is
    the second crowing). Mark mentions (14:30) the two
    cock-crowings. Matthew (26:34) alludes to that only which was
    emphatically the cock-crowing, viz, the second.