My eyes have prevented the night watchers. [1] The Psalmist here intimates, that he was more sedulously intent on meditating upon the law of God than watchmen of the night were to keep watch. Others are of opinion, that the verb svch, suach, is put for to discourse. If this opinion is admitted, the sense will be, that the Prophet, not from ostentation, but for the welfare of his brethren, was so desirous of communicating instruction, that he gave himself no rest. The word meditate is, however, more appropriate in this place; for the night is an unseasonable time for discoursing upon the law of God; but at that season, when alone, he silently recalled to his memory what he had previously learned, so that he passed no part of the night without meditating upon the law.

Footnotes

1 - The Hebrews divided the natural day into three portions--morning, noon, and evening -- which are mentioned by David as seasons in which he engaged in prayer. (Psalm 55:17.) They also divided the night into three parts, called "watches," consisting of four hours each, and commencing at our six o'clock in the evening. In Lamentations 2:19, we read of the first watch; or, as it is there designated, "the beginning of the watches;" in Judges 7:19, of "the middle watch;" and in Exodus 14:24, of "the morning watch." A similar division of the night seems to have been made by other ancient nations, as appears from the references made to it by Homer and the early Greek writers. The Greeks and Romans, however, in improving their military discipline, afterwards divided the night into four watches, each consisting of three hours; and when the Jews fell under the dominion of the latter people, they adopted from them this division of the night. Hence we read of "the fourth watch of the night" in Matthew 14:25. And the four watches are mentioned together in Mark 13:35: "Watch ye therefore: for ye know not when the master of the house cometh, at even, or at midnight, or at cock-crowing, or in the morning." The time at which each of these four watches began and ended is thus determined by Dr. Hales, who has written elaborately on the subject: "1. Opse, the late, began at sunset, and ended with the third hour of the night, including the evening-dawn, or twilight. It was also called opsia hora, eventide, Mark 11:11; or simply opsia, evening, John 20:19, etc. 2. Mesonuktion, the midnight, lasted from the third hour till midnight. 3. Alektorophonia, the cock-crowing, midnight till the third hour after, or the ninth hour of the night. It included the two cock-crowings, with the second or principal of which it ended. 4. Proi, the early, lasted from the ninth to the twelfth hor of the night, or sunrise, including the morning-dawn or twilight. It is also called proia, morning, or morningtide, (hora being understood,) John 18:28, etc. "When the Psalmist here declares, that his eyes prevented the nightwatches, we are to understand him as chiefly referring to the middle and morning watches, which falling at that period of the night when men in general are devoted to rest, envinced the strength, fervour, and self-sacrificing character of his devotions." -- Dr. Morison.

Mine eyes prevent the night watches - Luther renders this, "I wake up early." The Hebrew word means a "watch" - a part of the night, so called from military watches, or a dividing of the night to "keep guard." See the notes at Psalm 90:4. The idea of the psalmist here is, that he anticipated these regular divisions of the night in order that he might engage in devotion. Instead of waiting for their return, he arose for prayer before they recurred - so much did his heart delight in the service of God. The language would seem to be that of one who was accustomed to pray in these successive "watches" of the night - the early, the middle, and the dawn. This may illustrate what occurs in the life of all who love God. They will have regular seasons of devotion, but they will often anticipate those seasons. They will be in a state of mind which prompts them to pray; when nothing will meet their state of mind but prayer; and when they cannot wait for the regular and ordinary season of devotion - like a hungry man who cannot wait for the usual and regular hour of his meals. The meaning of the phrase, "mine eyes prevent," is that he awoke before the usual time for devotion.
That I might meditate in thy word - See the notes at Psalm 1:2.

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 Psalm 119:164 (note).

Mine eyes (b) prevent the [night] watches, that I might meditate in thy word.
(b) He was more earnest in the study of God's word, than they who kept the watch were in their charge.

Mine eyes prevent the night watches,.... The Targum is,
"the morning and evening watches.''
There were three of them; Kimchi interprets it of the second and third; the meaning is, that the psalmist was awake and employed in one religious exercise or another, praying, reading, or meditating; either before the watches were set, or however before the time that some of them took place, or at least before they were all over;
that I might meditate in thy word; he rose so early, in order to give himself up to meditation on the word of God; that he might be better instructed in the knowledge of divine things; that he might have solace and comfort from thence under his afflictions; and that he might be better furnished for the work of prayer; for the more familiar the word of God is to us, the better able we are to speak to God in his own language.

Watches - The middle watch, which was set in the middle of the night; and the morning watch, which was set some hours before the dawning of the day.