Albert Barnes Commentary Amos 5:24

"But let justice roll down as waters, and righteousness as a mighty stream." — Amos 5:24 (ASV)

But - (And) let judgment run down like water. (Literally, “roll,” English margin) The duties of either table include both, since there is no true love for man without the love of God, nor any real love or duty to God without the love of man. People will exchange their sins for other sins. They will not break them off unless they are converted to God. But the first outward step in conversion is to break off sin.

He bids them then let judgment, which had until then always been perverted in its course, roll on like a mighty tide of waters, sweeping before it all hindrances, obstructed by no power, turned aside by no bribery, but pouring on in one perpetual flow, reaching all, refreshing all, and righteousness like a mighty (or ceaseless) stream.

The word “ethan” may signify “strong” or “perennial.” For this reason, the seventh month, just before the early rain, was called “the month Ethanim” (1 Kings 8:2), that is, the month of the “perennial streams,” when they alone flowed. In the meaning “perennial,” it would stand tacitly contrasted with “streams which fail or lie.” True righteousness is not fitful, like an intermittent stream, vehement at one time, then disappearing, but continuous, unfailing.