Like the heath - Or, Like a destitute man. See the marginal reference note.

Flee, save your lives - The enemy is in full pursuit of you.
Be like the heath - כערוער caaroer, "like Aroer;" which some take for a city, others for a blasted or withered tree. It is supposed that a place of this name lay towards the north, in the land of the Ammonites, on a branch of the river Jabbok; surrounded by deserts. Save yourselves by getting into the wilderness, where the pursuing foe will scarcely think it worth his while to follow you, as the wilderness itself must soon destroy you.

Flee, save your lives, and be like the (e) bush in the wilderness.
(e) Hide yourselves in barren places, where the enemy will not pursue after you, (Jeremiah 17:6).

Flee, save your lives,.... These are either the words of the Moabites, their cry of destruction mentioned in the latter part of Jeremiah 48:5; who, seeing nothing but ruin before their eyes, advise one another to flee in all haste, and save their lives if possible, since nothing else could be saved: or else they are the words of the prophet, giving counsel to the Moabites to betake themselves to flight for the safety of their lives, these being in great danger; so Abarbinel; with whom others agree, only think they are spoken ironically; suggesting, that when they had endeavoured by flight to save their lives, it would be to no purpose; they should not escape the hands of their enemies; which seems to be the truest sense:
and be like the heath in the wilderness; which is called "erice", or "ling", which grows in waste places. Kimchi and Menachem in Jarchi interpret it of a tree that grows in dry and desert places; a low, naked, barren, fruitless shrub; signifying, that, when they were fled from their habitations, they should be as solitary and stripped of all their good things as such a bare and naked shrub in a desert. Kimchi's note is, that when they had left their cities and fled, their cities would be as the heath in the wilderness. The Targum is,
"and be ye as the tower of Aroer, "as they" who dwell in tents in the wilderness.''
Jarchi observes that the tower of Aroer was built in the wilderness, and there was no inhabitant round it but those that dwelt in tents; and, the tower standing where there was no inhabitant, it looked like a waste. The Septuagint version is very foreign, "as a wild ass in the wilderness"; which is followed by the Arabic version.

They exhort one another to flee.
heath--or the juniper (see on Jeremiah 17:6). MAURER translates, "Be like one naked in the wilderness." But the sense is, Live in the wilderness like the heath, or juniper; do not "trust in" walls (Jeremiah 48:7) [GROTIUS]. (Compare Matthew 24:16-18).

Only by a precipitate flight into the desert can the Moabites save even their lives. The summons to flee is merely a rhetorical expression for the thought that there is no safety to be had in the country. To ותּהינה in Jeremiah 48:6 we must supply נפשׁות as the subject: "your souls shall be." Ewald would change נפשׁכם into נפשׁיכם; but this proposal has against it the fact that the plural form נפשׁים is found in but a single case, Ezekiel 13:20, and נפשׁות everywhere else: besides, נפשׁ is often used in the singular of several persons, as in 2-Samuel 19:6, and may further be easily taken here in a distributive sense; cf. מלּטוּ אישׁ נפשׁו, Jeremiah 51:6. The assumption of C. B. Michaelis, Rosenmller, Maurer, and of the translators of our "Authorized" English Version, that תּהינה is the second person, and refers to the cities, i.e., their inhabitants, is against the context. ערוער cannot here be the name of a town, because neither Aroer in the tribe of Reuben, which was situated on the Arnon, nor Aroer of the tribe of Gad, which was before Rabbath-Ammon, lay in the wilderness; the comparison, too, of the fugitives to a city is unsuitable. The clause reminds us of Jeremiah 17:6, and ערוער = the ערער of that passage; the form found here is either an error of transcription caused by thinking of Aroer, or a play upon the name of the city, for the purpose of pointing out the fate impending over it.

And be - Save your lives, though all ye have be lost.