This verse continues with a description of the noise, the jumping, the eating, and the orderly advance of the locusts.
As with the rumbling of chariots is literally “Like the sound of chariots.” Good News Translation says “they rattle like chariots.” It uses “rattle” because this verb is fitting for the noise of both locusts and chariots and makes a better point of comparison. The whirring of the wings of flying locusts is also compared to the noise of chariots in Rev 9.9. A “chariot” is an open vehicle with two or four wheels, used in war or for traveling. It is harnessed to and drawn by two or four horses. The chariots here are war chariots. A war chariot is manned by a driver and usually another soldier. From its platform the soldier can shoot arrows, throw projectiles, or engage in sword combat. It provides speed of movement on the battlefield but is limited to relatively flat and unobstructed terrain. If a language does not have a special term for “war chariot,” it may be rendered “war carriage,” “horse-drawn war cart,” “war cart pulled by horses,” or “horse-drawn cart for fighting.”
They leap on the tops of the mountains: Leap renders a Hebrew verb that can mean “to dance, to skip about,” so it pictures the way in which locusts jump. For this line New International Version has “they leap over mountaintops.” New Jerusalem Bible appears to have a similar exaggeration with “they spring over the mountain tops,” and so does Revised English Bible with “they bound over the peaks.” As the locusts come from the north (verse 20), they first appear to the people of Jerusalem on the tops of the mountains north of Jerusalem, particularly Mount Scopus and the northern part of the Mount of Olives. In any case, the approach of the army of locusts is described in the form of an exaggeration or hyperbole to heighten the poetic impact of the discourse. Good News Translation reverses the order of the first two lines. In English it is more natural to mention first the thing compared, “As they leap on the tops of the mountains,” and then the comparison, “they rattle like chariots.”
Like the crackling of a flame of fire devouring the stubble: The locusts make a noise as they eat up the stubble. These lines compare that sound with the sound of fire. In Palestine, after the harvest the dry stubble is burned and makes a crackling noise. Like rumbling, crackling is literally “sound,” which is better translated in every instance by a term for the sound that fits the object making the sound. Flame of fire can normally be translated with a single word for “fire,” as in Good News Translation. In Hebrew, English, and some other languages, fire is said to “devour” or “eat” what it burns. Some languages will need to adjust this figurative language (see Joel 2.3 and 1.19). Stubble is the lower parts of dry stalks of grain left in the ground after harvest. Good News Translation expands it to “dry grass,” but most languages may not need to do this.
Like a powerful army drawn up for battle: A powerful army is literally “a mighty people.” The context makes it appropriate to translate “people” as army. It is powerful because of its large numbers (see 1.6). Advancing locusts on the ground often are lined up in rows, like an army drawn up for battle, ready to attack a city.
Even though the second and third comparisons are linked with the first one in Hebrew, the flow of the discourse will be more natural in many languages if they are translated as separate sentences (so Good News Translation). Such decisions also depend on whether translators are attempting to reproduce an equivalent poetic style in their language to duplicate the beauty and forcefulness of the biblical text in this section.
Quoted with permission from de Blois, Kees & Dorn, Louis. A Handbook on Joel. (UBS Helps for Translators). Miami: UBS, 2020. For this and other handbooks for translators see here .