Shout for joy, O heavens! And rejoice, O earth! Break forth into joyful shouting, O mountains! For the LORD has comforted His people And will have compassion on His afflicted. Promise to Zion (Isaiah 49:13)
Nothing can furnish us with better matter for songs of praise and thanksgiving. Let the whole creation join with us in songs of joy, for it shares with us in the benefits of the redemption, and all they can contribute to this sacred melody is little enough in return for such inestimable favors.
Let there be joy in heaven, and let the angels of God celebrate the praises of the great Redeemer; let the earth and the mountains, particularly the great ones of the earth, be joyful, and break forth into singing, for the earnest expectation of the creature that waits for the glorious liberty of the children of God shall now be abundantly answered. God’s people are the blessings and ornaments of the world, and therefore let there be universal joy, for God has comforted his people that were in sorrow and he will have mercy upon the afflicted because of his covenant. (Matthew Henry)