Here, 1. David professes the ardent affection he had to the word of God: "I have longed after thy precepts, not only loved them, and delighted in what I have already attained, but I have earnestly desired to know them more and do them better, and am still pressing forward towards perfection." Tastes of the sweetness of God's precepts will but set us a longing after a more intimate acquaintance with them. He appeals to God concerning this passionate desire after his precepts: "Behold, I have thus loved, thus longed; thou knowest all things, thou knowest that I am thus affected." 2. He prays for grace to enable him to answer this profession. "Thou hast wrought in me this languishing desire, put life into me, that I may prosecute it; quicken me in thy righteousness, in thy righteous ways, according to thy righteous promise." Where God has wrought to will he will work to do, and where he has wrought to desire he will satisfy the desire.

So shall I have wherewith to answer him that reproacheth me,.... Saying there is no help and salvation for him in God; asking where is his God, in whom he trusted? and where is the promise of salvation, on which he depended? To which an easy and ready answer might be given, when the mercies and salvation of God came unto him, and he clearly appeared to be interested in them; see Psa 3:2;

for I trust in thy word: in Christ the essential Word, the object of trust and confidence; or in the written word, it being divinely inspired and dictated by the Spirit of God, and so to be depended on as true and faithful; or rather God's word of promise concerning mercy, grace, and salvation, which God that has made is faithful and able to perform, as may be believed.