John Gill Bible Commentary

Thy righteousness is an everlasting righteousness,.... Or, "is for ever" (z). The rectitude of his nature, his faithfulness in his promises, and his kindness and beneficence to his people; and particularly the righteousness of God revealed in the Gospel; the righteousness of his Son, which he approves and accepts of, and imputes to him that believes. This is a righteousness that will last for ever, will never be abolished; it will answer for them that have it in a time to come; it is of use throughout the whole of life, at death, in the day of judgment, and to all eternity; see Dan 9:24; and thy law is the truth; or "thy doctrine"; or "thy word", as the Arabic version. The Scriptures are called the Scriptures of truth, Dan 10:21 they come from the God of truth, and all that is contained in them is truth; the legal part of them is truth, and so is the Gospel; that is called the word of truth, and truth itself: it is concerning Christ, who is the truth; and it is directed into and made effectual by the Spirit of truth, and contains in it many excellent truths; and is therefore deservedly valued and esteemed by all good men; see Joh 17:17. (z) "in seculum", Pagninus, Montanus, Gejerus; "in aeternum", V. L. Michaelis.