Reader! do observe two grand things here mentioned. First, Christ is the Preacher of his own gospel. Having performed the office of a priest, he is also the prophet of his church. And secondly, do observe moreover what Christ preached, namely righteousness, God's righteousness. Yes! this was the office to which the Most Holy was to be anointed, when he had finished transgression, and made an end of sin, to bring in an everlasting righteousness, and which righteousness was to be unto all, and upon all them that believe, for there is no difference. Compare Isaiah 61:1, with Luke 4:18. Compare Daniel 9:24, with Romans 3:12. And how truly lovely is it, when we hear Christ by the spirit of prophecy in this Psalm declaring, that he hath preached it, that he did not hide it in his heart, nor conceal the Father's loving-kindness and truth from his redeemed, both Jew and Gentile, which are the great congregation; and then turn to the gospel, and behold the Lord Jesus, in the days of his flesh, going about preaching salvation, and when returning to glory, giving a commission to his disciples to go into all the world and preach the gospel to every creature. Mark 16:15; Mark 16:15.
Related Commentaries of Psalms 40:9
Psalms 40:9-10
9 I have preached righteousness in the great congregation: lo, I have not refrained my lips, O LORD, thou knowest.
10 I have not hid thy righteousness within my heart; I have declared thy faithfulness and thy salvation: I have not concealed thy lovingkindness and thy truth from the great congregation.