Psalms 40:9 - Exposition

I have preached righteousness in the great congregation : rather, I have proclaimed righteousness. David has sung the praises of God in the "great congregation,'' and extolled his righteousness and truth ( Psalms 35:18 ). He has not "preached," in the modern sense of the word, since the preaching office was reserved for the priests and Levites. Lo, I have not refrained my lips; or, I will not refrain my lips. I will continue to glorify thee openly, and praise thy Name while I have my being ( Psalms 104:33 ). O Lord, thou knowest; i.e. thou knowest the truth of my statement as to the past, and the sincerity of my promise as to the future.