Observe here, 1. The good knowledge David had of the word of God; he knew it so well that he was ready to own, with the utmost satisfaction, that all God's commandments are not only righteous, but righteousness itself, the rule and standard of righteousness. 2. The good use he resolved to make of that knowledge: My tongue shall speak of thy word, not only utter praise for it to the glory of God, but discourse of it for the instruction and edification of others, as that which he himself was full of (for out of the abundance of the heart the mouth will speak) and as that which he desired others also might be filled with. The more we see of the righteousness of God's commandments the more industrious we should be to bring others acquainted with them, that they may be ruled by them. We should always make the word of God the governor of our discourse, so as never to transgress it by sinful speaking or sinful silence; and we should often make it the subject-matter of our discourse, that it may feed many and minister grace to the hearers.

I have gone astray like a lost sheep,.... In desert places, as it is the nature of sheep to do (o). A sheep he was, a sheep of Christ, given him by the Father; known by him, and that knew him; knew his voice, and followed him; a sheep of his hand, and of his pasture; one of the lost sheep of the house of Israel, who had been lost in Adam, though recovered by grace; and had gone astray before conversion, but now returned to the Shepherd and Bishop of souls; and since conversion had gone astray from the Shepherd and fold, from the word and precepts of it, through inadvertence, the prevalence of corruption, the snares of the world, and the temptations of Satan; which he both deprecates and owns, Psa 119:10; though it may be understood, as it is by many interpreters, of his being forced, by the persecutions of his enemies, to wander from the courts of God, and from place to place:

seek thy servant; as a shepherd does his sheep when gone astray, which will not return of itself unless sought after: thou art my Shepherd, as if he should say, look me up, restore my soul; suffer me not to wander from thee, and go astray from thy word and ordinances: and when he calls himself his servant, it carries in it an argument for being looked up and sought out; since he was his servant, not by nature, but by grace; not by force, but willingly; he was his and devoted to his service. And another follows:

for I do not forget thy commandments; he retained a knowledge of them, an affection for them, and a desire to observe them; though he had gone astray from them, either in a criminal way, through the power and prevalence of sin, or against his will, through the force of persecution.

(o) So Aristotle observes, Hist. Animal. l. 9. c. 3. the same word that is used for feeding sheep is also translated "wander", Num. xiv. 33. so "errant" is used by Virgil for feeding with security, Bucolic. Eclog. 2, Vid. Servium in ib.

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