Adam Clarke on Psalms 119:148

Mine eyes prevent - קדמו kiddemu, "go before the watches." Before the watchman proclaims the hour, I am awake, meditating on thy words. The Jews divided the night into three watches, which began at what we call six o'clock in the evening, and consisted each of four hours. The Romans taught them afterwards to divide it into four watches of three hours each; and to divide the day and night into twelve hours each; wherein different guards of soldiers were appointed to watch. At the proclaiming of each watch the psalmist appears to have risen and performed some act of devotion. For a remarkable custom of our Saxon ancestors, see the note on Psa 119:164 (note).