My tongue shall speak of thy word. Here the Psalmist says, that when he shall have profited in God's law he will also employ himself in teaching it to others. This order is undoubtedly to be observed, That divine truth take root in our hearts before we engage in the work of teaching it to others. Yet every man, according to the measure of his faith, ought to communicate to his brethren what he has received, that the doctrine, whose use and fruit God would have to be displayed for the common edification of the Church, may not be buried. There is added the reason which ought to stir up all the godly to declare the law of God -- namely, because by this means righteousness is spread abroad through the whole world. When the Prophet honors the commandments of God with the title of righteousness, he does not simply express his approbation of them, but he indirectly shows, that, until this rule bear sway in governing mankind, the whole world is one scene of sad and horrible confusion. Yet, let my readers judge whether the word answer or witness, which the Hebrew verb nh, anah, properly signifies, is not more suitable in this place than speak; bringing out this sense -- "My tongue shall bear witness or answer to thy word; because the true knowledge of righteousness is to be sought only in the word;" but in that case, it will be necessary to supply the letter l, lamed, in the word 'mrtk, imrathecha, that it may read -- to thy word.

My tongue shall speak of thy word - It shall speak of it in the language of praise; it shall speak of it in making it known to others.
For all thy commandments are righteousness - I see this; I feel it; and, therefore, I will speak of it. My impression that thy commandments are all righteous is so deep, that I cannot but speak of them. I must vindicate them; I must praise thee for them.

My tongue shall speak of thy word - There is a curious distinction here. In the preceding verse he says, "My lips shall utter;" here no reference is made to articulate sounds, except as affixed to musical notes. In this verse he says, "My tongue shall speak;" here articulate and intelligible words are intended. He first utters sounds connected with words expressive of his grateful feelings; in the second he speaks words, principally those which God himself had spoken, containing promises of support, purposes relative to the redemption of his people, and denunciations against their enemies.

My tongue shall speak of thy word,.... Of the word of God in general; of the truth of it, which he knew by certain experience; of the purity of it, tending to promote holiness of heart and life; of the power and efficacy of it, enlightening his mind, and working effectually in him; of the profit of it, to his learning, to his instruction, comfort, and refreshment; of the preciousness of it, being of more worth than thousands of gold and silver; and of the pleasantness of it, being sweeter than the honey or honeycomb, and more to be esteemed than one's necessary food; and of the promises of it in particular, of the worth and value of them, of their suitableness and use, and of the faithful fulfilment of them; and of the doctrines of the word, especially those which relate to the grace of God, and salvation by the Messiah; and also of the precepts of the word, as follows:
for all thy commandments are righteousness; not only righteous, but righteousness itself, being strictly just and equitable in the highest sense; and not only some of them, but all of them; see Psalm 119:128. Aben Ezra's paraphrase of the words is,
"I will teach the children of men thy word, that they may know that thy commandments are righteousness;''
which is not amiss: and to the same sense is Kimchi's note, who observes, that author of the Masorah interprets it of praise; as if he had said, My tongue shall praise thy word, because all of it is righteousness.

My tongue shall speak of thy word--literally, "answer Thy Word," that is, with praise, respond to Thy word. Every expression in which we praise God and His Word is a response, or acknowledgment, corresponding to the perfections of Him whom we praise.