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 17:1PROPHECY CONCERNING DAMASCUS AND ITS ALLY SAMARIA, that is, Syria and Israel, which had leagued together (seventh and eighth chapters). (Isa 17:1-11)
Damascus--put before Israel (Ephraim, Isa 17:3), which is chiefly referred to in what follows, because it was the prevailing power in the league; with it Ephraim either stood or fell (Isa. 7:1-25).
isa 17:2cities of Aroer--that is, the cities round Aroer, and under its jurisdiction [GESENIUS]. So "cities with their villages" (Jos 15:44); "Heshbon and all her cities" (Jos 13:17). Aroer was near Rabbahammon, at the river of Gad, an arm of the Jabbok (Sa2 24:5), founded by the Gadites (Num 32:34).
for flocks-- (Isa 5:17).
isa 17:3fortress . . . cease--The strongholds shall be pulled down (Samaria especially: Hos 10:14; Mic 1:6; Hab 1:10).
remnant of Syria--all that was left after the overthrow by Tiglath-pileser (Kg2 16:9).
as the glory of . . . Israel--They shall meet with the same fate as Israel, their ally.
isa 17:4glory of Jacob--the kingdom of Ephraim and all that they rely on (Hos 12:2; Mic 1:5).
fatness . . . lean--(See on Isa 10:16).
isa 17:5harvestman, &c.--The inhabitants and wealth of Israel shall be swept away, and but few left behind just as the husbandman gathers the corn and the fruit, and leaves only a few gleaning ears and grapes (Kg2 18:9-11).
with his arm--He collects the standing grain with one arm, so that he can cut it with the sickle in the other hand.
Rephaim--a fertile plain at the southwest of Jerusalem toward Beth-lehem and the country of the Philistines (Sa2 5:18-22).
isa 17:6in it--that is, in the land of Israel.
two or three . . . in the top--A few poor inhabitants shall be left in Israel, like the two or three olive berries left on the topmost boughs, which it is not worth while taking the trouble to try to reach.
isa 17:7look to his Maker--instead of trusting in their fortresses-- (Isa 17:3; Mic 7:7).
isa 17:8groves--A symbolical tree is often found in Assyrian inscriptions, representing the hosts of heaven ("Saba"), answering to Ashteroth or Astarte, the queen of heaven, as Baal or Bel is the king. Hence the expression, "image of the grove," is explained (Kg2 21:7).
images--literally, "images to the sun," that is, to Baal, who answers to the sun, as Astarte to the hosts of heaven (Kg2 23:5; Job 31:26).
isa 17:9forsaken bough--rather "the leavings of woods," what the axeman leaves when he cuts down the grove (compare Isa 17:6).
which they left because of--rather, "which (the enemies) shall leave for the children of Israel"; literally, "shall leave (in departing) from before the face of the children of Israel" [MAURER]. But a few cities out of many shall be left to Israel, by the purpose of God, executed by the Assyrian.
isa 17:10forgotten . . . God of . . . salvation . . . rock-- (Deu 32:15, Deu 32:18).
plants--rather, "nursery grounds," "pleasure-grounds" [MAURER].
set in--rather, "set them," the pleasure-grounds.
strange slips--cuttings of plants from far, and therefore valuable.
isa 17:11In the day . . . thy plant--rather, "In the day of thy planting" [HORSLEY].
shalt . . . make . . . grow--MAURER translates, "Thou didst fence it," namely, the pleasure-ground. The parallel clause, "Make . . . flourish," favors English Version. As soon as thou plantest, it grows.
in the morning--that is, immediately after; so in Psa 90:14, the Hebrew, "in the morning," is translated "early."
but . . . shall be a heap--rather, "but (promising as was the prospect) the harvest is gone" [HORSLEY].
in . . . day of grief--rather, "in the day of (expected) possession" [MAURER]. "In the day of inundation" [HORSLEY].
of desperate sorrow--rather, "And the sorrow shall be desperate or irremediable." In English Version "heap" and "sorrow" may be taken together by hendiadys. "The heap of the harvest shall be desperate sorrow" [ROSENMULLER].
The connection of this fragment with what precedes is: notwithstanding the calamities coming on Israel, the people of God shall not be utterly destroyed (Isa 6:12-13); the Assyrian spoilers shall perish (Isa 17:13-14).
isa 17:12SUDDEN DESTRUCTION OF A GREAT ARMY IN JUDEA (namely that of the Assyrian Sennacherib), AND ANNOUNCEMENT OF THE EVENT TO THE ETHIOPIAN AMBASSADORS. (Isa. 17:12-18:7)
Woe . . . multitude--rather, "Ho (Hark)! a noise of," &c. The prophet in vision perceives the vast and mixed Assyrian hosts (Hebrew, "many peoples," see on Isa 5:26): on the hills of Judah (so "mountains," Isa 17:13): but at the "rebuke" of God, they shall "flee as chaff."
to the rushing . . . that make--rather, "the roaring . . . roareth" (compare Isa 8:7; Jer 6:23).
isa 17:13shall . . . shall--rather, "God rebuketh (Psa 9:5) them, and they flee--are chased"; the event is set before the eyes as actually present, not future.
chaff of . . . mountains--Threshing floors in the East are in the open air on elevated places, so as to catch the wind which separates the chaff from the wheat (Psa 88:13; Hos 13:3).
rolling thing--anything that rolls: stubble.
isa 17:14eventide . . . before morning--fulfilled to the letter in the destruction "before morning" of the vast host that "at eveningtide" was such a terror ("trouble") to Judah; on the phrase see Psa 90:6; Psa 30:5.
he is not--namely, the enemy.
us--the Jews. A general declaration of the doom that awaits the foes of God's people (Isa 54:17).
Isaiah announces the overthrow of Sennacherib's hosts and desires the Ethiopian ambassadors, now in Jerusalem, to bring word of it to their own nation; and he calls on the whole world to witness the event (Isa 18:3). As Isa 17:12-14 announced the presence of the foe, so Isa 18:1-7 foretells his overthrow.