Charles H. Spurgeon on Psalms 108:2

When the Hebrew captives were sitting in sorrow "by the waters of Babylon", they wept, and hung their harps on the willows, and could not be prevailed upon by the conquerors to sing "the songs of Zion in that land" (Ps 137:1,4). But when "the Lord turned again the captivity of Zion, then was their mouth filled with laughter and their tongue with singing" (Ps 126:1-2). Then the psaltery and harp of former generations awoke (Ps 108:2). The old songs revived on their lips, and the melodies of David acquired new charms for them. —Christopher Wordsworth.