heavens declare his righteousness
97:6 heavens declare his righteousness. Psalms 95–100 form a magnificent unit of praise, all centered on the future triumph of the Lord when He comes to purge the world of wickedness and all the effects of the age-long curse. Appropriately, this verse is the central verse of these six psalms. When He comes from heaven, all the people will see His glory (note also Matthew 24:30; Revelation 1:7), and acknowledge His righteousness.
Psalm 98 (title) A Psalm. This is the only psalm with the simple title, “A Psalm.” It is a special song of joy, with the word “joyful noise” occurring twice (Psalm 98:4,6). The same word (Hebrew rua) occurs in the first verses of the first and final psalms in this unique sextet of triumph songs (Psalms 95–100). The same word is also used when the angels “shouted for joy” as the Lord laid the foundations of the earth (Job 38:7).