Commentaries
89:15-18 Happy are those who so know the joyful sound of the gospel as to obey it; who experience its power upon their hearts, and bring forth the fruit of it in their lives. Though believers are nothing in themselves, yet having all in Christ Jesus, they may rejoice in his name. May the Lord enable us to do so. The joy of the Lord is the strength of his people; whereas unbelief dispirits ourselves and discourages others. Though it steals upon us under a semblance of humility, yet it is the very essence of pride. Christ is the Holy One of Israel; and in him was that peculiar people more blessed than in any other blessing.
15. His government of righteousness is served by "mercy" and "truth" as ministers (Ps 85:10-13).
know the joyful sound—understand and appreciate the spiritual blessings symbolized by the feasts to which the people were called by the trumpet (Le 25:9, &c.).
walk … countenance—live in His favor (Ps 4:6; 44:3).