Ellicott's Commentary for English Readers - Psalms 126:5
(5) Joy.—Rather, singing, as in Psalms 126:2. The harvest-home songs are contrasted with the anxiety of the seed-time. Probably the poet found the proverbial saying already current, but he has touched it with the consecrating hand till it has become only less precious than the saying of Divine lips, “Blessed are they that mourn, for they shall be comforted.” read more
John Dummelow's Commentary on the Bible - Psalms 126:1-6
A song of those who have been redeemed (from exile), and a hopeful prayer for those who have not yet returned.1. Turned again the captivity of Zion] either, brought back the exiles who returned to Zion, or, turned again the fortunes of Zion, i.e. perhaps, set her free from foreign yoke.4. Turn again our captivity] perhaps, ’bring back the exiles.’ As the streams in the south] i.e. like the hill streams in the arid S. land of Judah (the Negeb), dry for a time in summer but becoming suddenly... read more