Joel 1:4 - Ellicott's Commentary On The Whole Bible

That which the palmerworm hath left. — The picture is introduced suddenly and graphically. “Behold the desolation!” “Note the cause.” The earth is bared by locusts beyond all previous experience. There were different sorts of locusts; as many as ninety have been reckoned. The four names, palmerworm, locust, cankerworm, caterpiller, indicate different swarms of the insect. The first — Gazam — points to its voracity; the second — Arbeh — its multitude; the third — Yelek — its manner of “licking up” the grass like cattle; the fourth — Chasil — its destructive effect. The number enumerated, four, draws attention to the “four sore judgments” with which Ezekiel was instructed to threaten Jerusalem, and to the four foreign invasions by the Assyrians, Chaldæans, Macedonians, and Romans.