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 21:1REPETITION OF THE ASSURANCE GIVEN IN THE THIRTEENTH AND FOURTEENTH CHAPTERS TO THE JEWS ABOUT TO BE CAPTIVES IN BABYLON, THAT THEIR ENEMY SHOULD BE DESTROYED AND THEY BE DELIVERED. (Isa 21:1-10)
desert--the champaign between Babylon and Persia; it was once a desert, and it was to become so again.
of the sea--The plain was covered with the water of the Euphrates like a "sea" (Jer 51:13, Jer 51:36; so Isa 11:15, the Nile), until Semiramis raised great dams against it. Cyrus removed these dykes, and so converted the whole country again into a vast desert marsh.
whirlwinds in the south-- (Job 37:9; Zac 9:14). The south wind comes upon Babylon from the deserts of Arabia, and its violence is the greater from its course being unbroken along the plain (Job 1:19).
desert--the plain between Babylon and Persia.
terrible land--Media; to guard against which was the object of Nitocris' great works [HERODOTUS, 1.185]. Compare as to "terrible" applied to a wilderness, as being full of unknown dangers, Deu 1:29.
isa 21:2dealeth treacherously--referring to the military stratagem employed by Cyrus in taking Babylon. It may be translated, "is repaid with treachery"; then the subject of the verb is Babylon. She is repaid in her own coin; Isa 33:1; Hab 2:8, favor this.
Go up--Isaiah abruptly recites the order which he hears God giving to the Persians, the instruments of His vengeance (Isa 13:3, Isa 13:17).
Elam--a province of Persia, the original place of their settlement (Gen 10:22), east of the Euphrates. The name "Persia" was not in use until the captivity; it means a "horseman"; Cyrus first trained the Persians in horsemanship. It is a mark of authenticity that the name is not found before Daniel and Ezekiel [BOCHART].
thereof--the "sighing" caused by Babylon (Isa 14:7-8).
isa 21:3Isaiah imagines himself among the exiles in Babylon and cannot help feeling moved by the calamities which come on it. So for Moab (Isa 15:5; Isa 16:11).
pain--(Compare Isa 13:8; Eze 30:4, Eze 30:19; Nah 2:10).
at the hearing--The Hebrew may mean, "I was so bowed down that I could not hear; I was so dismayed that I could not see" (Gen 16:2; Psa 69:23) [MAURER].
isa 21:4panted--"is bewildered" [BARNES].
night of my pleasure--The prophet supposes himself one of the banqueters at Belshazzar's feast, on the night that Babylon was about to be taken by surprise; hence his expression, "my pleasure" (Isa 14:11; Jer 51:39; Dan. 5:1-31).
isa 21:5Prepare the table--namely, the feast in Babylon; during which Cyrus opened the dykes made by Semiramis to confine the Euphrates to one channel and suffered them to overflow the country, so that he could enter Babylon by the channel of the river. Isaiah first represents the king ordering the feast to be got ready. The suddenness of the irruption of the foe is graphically expressed by the rapid turn in the language to an alarm addressed to the Babylonian princes, "Arise," &c. (compare Isa 22:13). MAURER translates, "They prepare the table," &c. But see Isa 8:9.
watch in . . . watchtower--rather, "set the watch." This done, they thought they might feast in entire security. Babylon had many watchtowers on its walls.
anoint . . . shield--This was done to prevent the leather of the shield becoming hard and liable to crack. "Make ready for defense"; the mention of the "shield" alone implies that it is the Babylonian revellers who are called on to prepare for instant self-defense. HORSLEY translates, "Grip the oiled shield."
isa 21:6Go, set a watchman, let him declare what he seeth--God's direction to Isaiah to set a watchman to "declare" what he sees. But as in Isa 21:10, Isaiah himself is represented as the one who "declared." HORSLEY makes him the "watchman," and translates, "Come, let him who standeth on the watchtower report what he seeth."
isa 21:7chariot, &c.--rather, "a body of riders," namely, some riding in pairs on horses (literally, "pairs of horsemen," that is, two abreast), others on asses, others on camels (compare Isa 21:9; Isa 22:6). "Chariot" is not appropriate to be joined, as English Version translates, with "asses"; the Hebrew means plainly in Isa 21:7, as in Isa 21:9, "a body of men riding." The Persians used asses and camels for war [MAURER]. HORSLEY translates, "One drawn in a car, with a pair of riders, drawn by an ass, drawn by a camel"; Cyrus is the man; the car drawn by a camel and ass yoked together and driven by two postilions, one on each, is the joint army of Medes and Persians under their respective leaders. He thinks the more ancient military cars were driven by men riding on the beasts that drew them; Isa 21:9 favors this.
isa 21:8A lion--rather, "(The watchman) cried, I am as a lion"; so as is understood (Isa 62:5; Psa 11:1). The point of comparison to "a lion" is in Rev 10:3, the loudness of the cry. But here it is rather his vigilance. The lion's eyelids are short, so that, even when asleep, he seems to be on the watch, awake; hence he was painted on doors of temples as the symbol of watchfulness, guarding the place (Hor. Apollo) [HORSLEY].
isa 21:9chariot of men--chariots with men in them; or rather, the same body of riders, horsemen two abreast, as in Isa 21:7 [MAURER]. But HORSLEY, "The man drawn in a car with a pair of riders." The first half of this verse describes what the watchman sees; the second half, what the watchman says, in consequence of what he sees. In the interval between Isa 21:7 and Isa 21:9, the overthrow of Babylon by the horsemen, or man in the car, is accomplished. The overthrow needed to be announced to the prophet by the watchman, owing to the great extent of the city. HERODOTUS (1.131) says that one part of the city was captured some time before the other received the tidings of it.
answered--not to something said previously, but in reference to the subject in the mind of the writer, to be collected from the preceding discourse: proclaimeth (Job 3:2, Margin; Dan 2:26; Act 5:8).
fallen . . . fallen--The repetition expresses emphasis and certainty (Psa 92:9; Psa 93:3; compare Jer 51:8; Rev 18:2).
images--Bel, Merodach, &c. (Jer 50:2; Jer 51:44, Jer 51:52). The Persians had no images, temples, or altars, and charged the makers of such with madness [HERODOTUS 1.131]; therefore they dashed the Babylonian "images broken unto the ground."
isa 21:10my threshing--that is, my people (the Jews) trodden down by Babylon.
corn of my floor--Hebrew, "my son of the floor," that is, my people, treated as corn laid on the floor for threshing; implying, too, that by affliction, a remnant (grain) would be separated from the ungodly (chaff) [MAURER]. HORSLEY translates, "O thou object of my unremitting prophetic pains." See Isa 28:27-28. Some, from Jer 51:33, make Babylon the object of the threshing; but Isaiah is plainly addressing his countrymen, as the next words show, not the Babylonians.
One out of Seir asks, What of the night? Is there a hope of the dawn of deliverance? Isaiah replies, The morning is beginning to dawn (to us); but night is also coming (to you). Compare Psa 137:7. The Hebrew captives would be delivered, and taunting Edom punished. If the Idumean wish to ask again, he may do so; if he wishes an answer of peace for his country, then let him "return (repent), come" [BARNES].
isa 21:11A PROPHECY TO THE IDUMEANS WHO TAUNTED THE AFFLICTED JEWS IN THE BABYLONISH CAPTIVITY. (Isa 21:11-12)
Dumah--a tribe and region of Ishmael in Arabia (Gen 25:14; Ch1 1:30); now called Dumah the Stony, situated on the confines of Arabia and the Syrian desert; a part put for the whole of Edom. VITRINGA thinks "Dumah," Hebrew, "silence," is here used for Idumea, to imply that it was soon to be reduced to silence or destruction.
Seir--the principal mountain in Idumea, south of the Dead Sea, in Arabia-PetrÃ&brvbr;a. "He calleth" ought to be rather, "There is a call from Seir."
to me--Isaiah. So the heathen Balak and Ahaziah received oracles from a Hebrew prophet.
Watchman--the prophet (Isa 62:6; Jer 6:17), so called, because, like a watchman on the lookout from a tower, he announces future events which he sees in prophetic vision (Hab 2:1-2).
what of the night--What tidings have you to give as to the state of the night? Rather, "What remains of the night?" How much of it is past? [MAURER]. "Night" means calamity (Job 35:10; Mic 3:6), which, then, in the wars between Egypt and Assyria, pressed sore on Edom; or on Judah (if, as BARNES thinks, the question is asked in mockery of the suffering Jews in Babylon). The repetition of the question marks, in the former view, the anxiety of the Idumeans.
isa 21:12Reply of the prophet, The morning (prosperity) cometh, and (soon after follows) the night (adversity). Though you, Idumeans, may have a gleam of prosperity, it will soon be followed by adversity again. Otherwise, as BARNES, "Prosperity cometh (to the Jews) to be quickly followed by adversity (to you, Idumeans, who exult in the fall of Jerusalem, have seized on the southern part of their land in their absence during the captivity, and now deride them by your question)" (Isa 34:5-7). This view is favored by Oba 1:10-21.
if ye will inquire, inquire--If ye choose to consult me again, do so (similar phrases occur in Gen 43:14; Kg2 7:4; Est 4:16).
return, come--"Be converted to God (and then), come" [GESENIUS]; you will then receive a more favorable answer.
Probably in the wars between Assyria and Egypt; Idumea and Arabia lay somewhat on the intermediate line of march.
isa 21:13PROPHECY THAT ARABIA WOULD BE OVERRUN BY A FOREIGN FOE WITHIN A YEAR. (Isa 21:13-17)
upon--that is, respecting.
forest--not a grove of trees, but a region of thick underwood, rugged and inaccessible; for Arabia has no forest of trees.
travelling companies--caravans: ye shall be driven through fear of the foe to unfrequented routes (Isa 33:8; Jdg 5:6; Jer 49:8 is parallel to this passage).
Dedanim--In North Arabia (Gen 25:3; Jer 25:23; Eze 25:13; Eze 27:20; a different "Dedan" occurs Gen 10:7).
isa 21:14Tema--a kindred tribe: an oasis in that region (Jer 25:23). The Temeans give water to the faint and thirsting Dedanites; the greatest act of hospitality in the burning lands of the East, where water is so scarce.
prevented--that is, anticipated the wants of the fugitive Dedanites by supplying bread (Gen 14:18).
their bread--rather, "his (the fugitive's) bread"; the bread due to him, necessary for his support; so "thy grave" (Isa 14:19), [MAURER].
isa 21:15they--the fugitive Dedanites and other Arabs.
isa 21:16years of . . . hireling--(See on Isa 16:14).
Kedar--a wandering tribe (Psa 120:5). North of Arabia-PetrÃ&brvbr;a, and south of Arabia-Deserta; put for Arabia in general.
isa 21:17residue . . . diminished--The remnant of Arab warriors, famous in the bow, left after the invasion, shall be small.
That by Sennacherib, in the fourteenth year of Hezekiah; Isa 22:8-11, the preparations for defense and securing of water exactly answer to those in Ch2 32:4-5, Ch2 32:30. "Shebna," too (Isa 22:15), was scribe at this time (Isa 36:3) [MAURER]. The language of Isa 22:12-14, as to the infidelity and consequent utter ruin of the Jews, seems rather to foreshadow the destruction by Nebuchadnezzar in Zedekiah's reign, and cannot be restricted to Hezekiah's time [LOWTH].