A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
isa 15:1THE FIFTEENTH AND SIXTEENTH CHAPTERS FORM ONE PROPHECY ON MOAB. (Isa 15:1-9)
Because--rather, "Surely"; literally, "(I affirm) that" [MAURER].
night--the time best suited for a hostile incursion (Isa 21:4; Jer 39:4).
Ar--meaning in Hebrew, "the city"; the metropolis of Moab, on the south of the river Arnon.
Kir--literally, "a citadel"; not far from Ar, towards the south.
Bajith--rather, "to the temple" [MAURER]; answering to the "sanctuary" (Isa 16:12), in a similar context.
to Dibon--Rather, as Dibon was in a plain north of the Arnon, "Dibon (is gone up) to the high places," the usual places of sacrifice in the East. Same town as Dimon (Isa 15:9).
to weep--at the sudden calamity.
over Nebo--rather "in Nebo"; not "on account of" Nebo (compare Isa 15:3) [MAURER]. The town Nebo was adjacent to the mountain, not far from the northern shore of the Dead Sea. There it was that Chemosh, the idol of Moab, was worshipped (compare Deu 34:1).
Medeba--south of Heshbon, on a hill east of Jordan.
baldness . . . beard cut off--The Orientals regarded the beard with peculiar veneration. To cut one's beard off is the greatest mark of sorrow and mortification (compare Jer 48:37).
isa 15:3tops of . . . houses--flat; places of resort for prayer, &c., in the East (Act 10:9).
weeping abundantly--"melting away in tears." HORSLEY prefers "descending to weep." Thus there is a "parallelism by alternate construction" [LOWTH], or chiasmus; "howl" refers to "tops of houses." "Descending to weep" to "streets" or squares, whither they descend from the housetops.
isa 15:4Heshbon--an Amorite city, twenty miles east of Jordan; taken by Moab after the carrying away of Israel (compare Jer. 48:1-47).
Elealeh--near Heshbon, in Reuben.
Jahaz--east of Jordan, in Reuben. Near it Moses defeated Sihon.
therefore--because of the sudden overthrow of their cities. Even the armed men, instead of fighting in defense of their land, shall join in the general cry.
life, &c.--rather, "his soul is grieved" (Sa1 1:8) [MAURER].
isa 15:5My--The prophet himself is moved with pity for Moab. Ministers, in denouncing the wrath of God against sinners, should do it with tender sorrow, not with exultation.
fugitives--fleeing from Moab, wander as far as to Zoar, on the extreme boundary south of the Dead Sea. HORSLEY translates, "her nobility," or "rulers" (Hos 4:18).
heifer, &c.--that is, raising their voices "like a heifer" (compare Jer 48:34, Jer 48:36). The expression "three years old," implies one at its full vigor (Gen 15:9), as yet not brought under the yoke; as Moab heretofore unsubdued, but now about to be broken. So Jer 31:18; Hos 4:13. MAURER translates, "Eglath" (in English Version, "a heifer") Shelishijah (that is, the third, to distinguish it from two others of the same name).
by the mounting up--up the ascent.
Luhith--a mountain in Moab.
Horonaim--a town of Moab not far from Zoar (Jer 48:5). It means "the two poles," being near caves.
cry of destruction--a cry appropriate to the destruction which visits their country.
isa 15:6For--the cause of their flight southwards (Kg2 3:19, Kg2 3:25). "For" the northern regions and even the city Nimrim (the very name of which means "limpid waters," in Gilead near Jordan) are without water or herbage.
isa 15:7Therefore--because of the devastation of the land.
abundance--literally, "that which is over and above" the necessaries of life.
brook of . . . willows--The fugitives flee from Nimrim, where the waters have failed, to places better watered. Margin has "valley of Arabians"; that is, to the valley on the boundary between them and Arabia-PetrÃ&brvbr;a; now Wady-el Arabah. "Arabia" means a "desert."
isa 15:8Eglaim-- (Eze 47:10), En-eglaim. Not the Agalum of EUSEBIUS, eight miles from Areopolis towards the south; the context requires a town on the very borders of Moab or beyond them.
Beer-elim--literally, "the well of the Princes"--(so Num 21:16-18). Beyond the east borders of Moab.
isa 15:9Dimon--same as Dibon (Isa 15:2). Its waters are the Arnon.
full of blood--The slain of Moab shall be so many.
bring more--fresh calamities, namely, the "lions" afterwards mentioned (Kg2 17:25; Jer 5:6; Jer 15:3). VITRINGA understands Nebuchadnezzar as meant by "the lion"; but it is plural, "lions." The "more," or in Hebrew, "additions," he explains of the addition made to the waters of Dimon by the streams of blood of the slain.