Rashi
Jewish
1040–1105
“Battle formations. Menachem interprets "strategists, military tactitians." He relates this to "The locust has no king, yet he advances entirely 'in formation'." The meaning is 'battle formations." Another interpretation, Concerning the clatter of pebbles amidst the watering places. When you would walk amidst the watering places to draw water, you were terrified by the clatter of the pebbles smoothed by the stream, "cailloux" in old French. When stepped on, they emit a noise, and you were afraid that your presence would be sensed by your enemies. Now, however, such fears are baseless, and this is why you are commanded to offer thanks to His Name. Pebbles. This refers to pebbles smoothed by a stream, as in "He ground with pebbles."”