My eyes have failed for thy salvation. [1] In the first place he testifies, that he had been afflicted with severe troubles, and that not for a short time only, but for a period so protracted as might have exhausted his patience and occasioned despondency. But so far was this from being the effect they produced, that he declares that in all these long and wearisome conflicts his heart had never sunk into despair. We have before explained failing for salvation as denoting that although there was no prospect of an end to his calamities, and although despair presented itself on every side, yet he strove against temptation even to the fainting of his soul. Should we understand the past tense of the verb as put for the present, in which sense it seems to be employed, the Prophet in that case intimates, that his eyes fail him not because they become fatigued, but because through earnest looking they contract as it were a dimness, and that yet he does not cease to wait continually for the salvation of God. In short, the failing of his eyes indicates perseverance combined with severe and arduous effort, and it is opposed to the momentary ardor of those who immediately faint, if God does not grant their requests. This expression also denotes a painful earnestness, which almost consumes all the senses. As to the term salvation, he does not limit it to one kind of help, but comprehends under it the continual course of God's grace, until he put his believing people in the possession of complete salvation. He expresses the manner in which he waited for salvation, which was by depending upon God's word in which two things are to be attended to, first, that we can only be said to wait for salvation from God, when, confiding in his promises, we actually betake ourselves to him for protection; and secondly, that we then only yield to God the praise of salvation, when we continue to keep our hope firmly fixed on his word. This is the way in which He is to be sought; and although he may conceal from our view the working of his hand, we ought to repose in his bare promises. This is the reason why David calls God's word righteous. He would hereby confirm his faith in the truth of the divine promises for God in promising liberally does not cherish in his people delusive expectations.

Footnotes

1 - "In times of great sorrow, when the heart is oppressed with care, and when danger threatens on every side, the human eye expresses with amazing accuracy the distressing and anguished emotions of the soul. The posture here described is that of an individual who perceives himself surrounded with enemies of the most formidable character, who feels his own weakness and insufficiency to enter into conflict with them, but who is eagerly looking for the arrival of a devoted and powerful friend, who has promised to succor him in the hour of his calamity." -- Dr. Morison.

Mine eyes fail for thy salvation - See the notes at Psalm 119:81-82.
And for the word of thy righteousness - Thy righteous word - that it may be made known to me, and that I may see its beauty and enjoy it.

Mine eyes fail - See on Psalm 119:82 (note).

Mine eyes fail for that salvation,.... For temporal salvation or deliverance from oppressors; and for spiritual salvation, for views of an interest in it, the joys and comforts of it; and for the Messiah, the author of it; whom he was looking wistfully for, but, not coming so soon as expected, his eyes were tired and weary, and ready to fail, and his heart to faint; See Gill on Psalm 119:81;
and for the word of thy righteousness; for the word of promise, which the righteousness or faithfulness of God was engaged to perform; or for the law of God, the rule of righteousness, and which shows what righteousness God requires; and for the bringing in of that righteousness of the Messiah, which could answer its demands; or for the Gospel, and more clear administration of it, which is called the word of righteousness, Hebrews 5:13; in which the righteousness of God is revealed; the righteousness which Christ, who is God as well as man, has wrought out; and which his Father has approved of, accepted, and imputes to his people, and justifies them with; and which word also teaches men to live soberly, righteously, and godly.

The word - For the performance of thy faithful or merciful promise.