Psalms 40:9

"I have proclaimed glad tidings of righteousness in the great assembly;

Lo I will not refrain my lips,

O Jehovah, thou knewest."

There can be little doubt that this passage, as Matthew Henry said, is a reference, "To the coming of the great salvation,"[24] and that `great salvation' began to be spoken by the Lord (Hebrews 2:3), and not by David. "This is a reference to the Gospel of Christ which is preached to all nations."[25]

"In the great assembly" (Psalms 40:9). This is a much more understandable statement as a reference to the fantastically large crowds of the people who heard the preaching of Jesus Christ than it ever could be as applied to any preaching ever done by David.