Isaiah 34:6

6 The sword of the LORD is bathed in blood, it is covered with fat— the blood of lambs and goats, fat from the kidneys of rams. For the LORD has a sacrifice in Bozrah and a great slaughter in the land of Edom.

Read Isaiah 34:6 Using Other Translations

The sword of the LORD is filled with blood, it is made fat with fatness, and with the blood of lambs and goats, with the fat of the kidneys of rams: for the LORD hath a sacrifice in Bozrah, and a great slaughter in the land of Idumea.
The LORD has a sword; it is sated with blood; it is gorged with fat, with the blood of lambs and goats, with the fat of the kidneys of rams. For the LORD has a sacrifice in Bozrah, a great slaughter in the land of Edom.
The sword of the LORD is drenched with blood and covered with fat— with the blood of lambs and goats, with the fat of rams prepared for sacrifice. Yes, the LORD will offer a sacrifice in the city of Bozrah. He will make a mighty slaughter in Edom.

What does Isaiah 34:6 mean?

John Gill's Exposition of the Bible
Isaiah 34:6

The sword of the Lord is filled with blood
Multitudes being slain by it; the "Lord" here is that divine Person that is described as a warrior, as a General of an army, with a sharp sword, by whom many are slain, such a number as that it is filled with the blood of them, ( Revelation 19:11-16 Revelation 19:21 ) : it is made fat with fatness:
not only filled with the blood, but fattened by it; the allusion is to ravenous creatures gorged and sated with the blood of others, and thereby made fat; perhaps this may refer to Christian princes, the sword in the hand of the Lord, who shall be enriched with the plunder and spoil of the antichristian states: [and] with the blood of lambs and goats, with the fat of the
kidneys of rams.
The Targum is,

``with the blood of kings and governors, with the fat of the kidneys princes;''
and Jarchi interprets them, of princes and rulers; but rather the common people are designed, or the common soldiers in the army, or however the inferior officers of it; kings, princes, and generals, being intended in the following verse ( Isaiah 34:7 ) . It denotes the great carnage of all sorts and ranks of men made at this time, and which is described in ( Revelation 19:18 ) : for the Lord hath a sacrifice in Bozrah, and a great slaughter in
the land of Idumea:
there seems to be two Bozrahs the Scripture speaks of, the one in Moab, ( Jeremiah 48:24 ) and another in Edom, ( Isaiah 63:1 ) which is here meant, and was a chief city of the Edomites, and signifies a fortress, being no doubt a place well fortified; this is the Bostra of Ptolemy F11, and which he places in Arabia Petraea. Aben Ezra says that some interpret it of Constantinople, the metropolis of the Ottoman empire; but it is best to understand it of Rome, as Menasseh ben Israel F12 does, and Idumea of the whole Roman jurisdiction; Rome being the chief city of the antichristian states, that great city, which John in his Revelation describes as reigning over the kings of the earth; here and in all the antichristian kingdoms will be a great "slaughter" of men, called a "sacrifice" of the Lord, because by his order and direction, and for the honour of his justice, and being acceptable to him; and perhaps there may be an allusion to the blood sacrifices being the Lord's; this slaughter and sacrifice is called the supper of the great God, ( Revelation 19:17 ) .
FOOTNOTES:

F11 Geograph. l. 5. c. 17.
F12 Spes Israelis, sect. 30. p. 91.
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