I have preached righteousness in the great congregation - I have main tained and defended the principles of righteousness and truth among assembled multitudes. it would be difficult to see how this could be applied to David himself, or on what occasion of his life this could be said of him; but no one can doubt that this is applicable to the Messiah:

(a) He was a preacher.

(b) He addressed vast multitudes.

(c) Before them all, and at all times, he maintained and illustrated the great principles of "righteousness" as demanded by the law of God, and unfolded the way in which all those multitudes might become righteous before God.

Lo, I have not refrained my lips - I have not closed my lips. I have not kept back the truth.

O Lord, thou knowest - He could make this solemn appeal to God as the Searcher of hearts, in proof that he had faithfully uttered all that had been required of him in making known the will of God. Compare John 17:4, John 17:6,John 17:8, John 17:14, John 17:26.

I have preached righteousness - I think it best to refer these words to Christ and his apostles. In consequence of his having become a sacrifice for sin, the Jewish sacrificial system being ended, the middle wall of partition was broken down, and the door of faith, the doctrine of justification by faith, opened to the Gentiles. Hence the Gospel was preached in all the world, and the mercy of God made known to the Gentiles; and thus righteousness - justification by faith, was preached in the great congregation - to Jews and Gentiles, throughout the Roman empire.

The great congregation, both in this and the following verse, I think, means the Gentiles, contradistinguished from the Jews.

The word righteousness means the plan or method of salvation by Jesus Christ - God's method of justifying sinners by faith, without the deeds of the law. See Romans 3:25-26 (note), and the notes there.

I have preached righteousness in the great congregation,.... Not the righteousness which the law requires men to do; but the righteousness which Christ himself wrought out, for the justification of them that believe; this he was a preacher, as well as the author of, and is part of the glad tidings he was anointed to preach, Isaiah 61:1; and the word (n) here used signifies, for the most part, the publishing of good tidings; and this our Lord did publicly, before all the people, in the synagogues of the Jews, and in the temple, whither the people in great numbers resorted; especially at the three great festivals in the year; the feasts of passover, pentecost, and tabernacles, when all the males were obliged to appear, and made up a great congregation indeed; see John 2:23;

lo, I have not refrained my lips, O Lord, thou knowest; Christ appeals to his divine Father, the searcher of hearts, and trier of reins, for the truth of this; that he had not laid any restraint upon his lips, nor kept back anything in his ministry that was profitable; but had taught the way of God in great integrity and sincerity; had opened his mouth, and spoke freely and fully, and used great plainness of speech.

(n) Sept. "evangelizavi", Schmidt, Michaelis; "I have preached the glad tidings of justice", Ainsworth.

I have preached righteousness in the {h} great congregation: lo, I have not refrained my lips, O LORD, thou knowest.

(h) In the Church assembled in the sanctuary.

40:9 Righteousness - Thy faithfulness. Great congregation - In the most public and solemn assemblies: not only to the Jews, but also to all nations; to whom Christ preached by his apostles, as is observed Eph 2:17. Not refrained - From preaching it, even to the face of mine enemies.

9, 10. I have preached-literally, "announced good tidings." Christ's prophetical office is taught. He "preached" the great truths of God's government of sinners.

40:6-10 The psalmist foretells that work of wonder, redemption by our Lord Jesus Christ. The Substance must come, which is Christ, who must bring that glory to God, and that grace to man, which it was impossible the sacrifices should ever do. Observe the setting apart of our Lord Jesus to the work and office of Mediator. In the volume, or roll, of the book it was written of him. In the close rolls of the Divine decrees and counsel, the covenant of redemption was recorded. Also, in all the volumes of the Old Testament something was written of him, Joh 19:28. Now the purchase of our salvation is made, the proclamation is sent forth, calling us to come and accept it. It was preached freely and openly. Whoever undertook to preach the gospel of Christ, would be under great temptation to conceal it; but Christ, and those he calls to that work, are carried on in it. May we believe his testimony, trust his promise, and submit to his authority.