What is the supper of the great God?
The Supper of the Great God is the gruesome feast held after the Battle of Armageddon, in which the birds of the air and beasts of the field are summoned by an angel to devour the flesh of all who were slain in that great war, kings, captains, mighty men, horses and riders, both free and bond, small and great.
After Jesus and the armies of Heaven defeat the Antichrist, the false prophet, and the gathered armies of the earth at Armageddon, another feast is announced, quite different from the joyful Marriage Supper of the Lamb that preceded the battle. This is the Supper of the Great God, also called the Feast of the Birds. An angel stands in the sun and cries with a loud voice to all the fowls that fly in the midst of heaven, calling them to come and gather together unto the supper of the great God.
At this supper the birds and beasts are invited to eat the flesh of kings, captains, mighty men, horses and their riders, and of all men, both free and bond, both small and great. It is the flesh of the armies slain by the sword that proceeds from the mouth of the One who rides the white horse, Faithful and True, the Word of God, King of Kings and Lord of Lords. The beast and the false prophet themselves are not part of this feast; they are cast alive into the lake of fire, while the remnant of their armies are slain and become the food for the fowls.
Ezekiel's prophecy corroborates this scene, describing the same great sacrifice upon the mountains of Israel, where every feathered fowl and every beast of the field are gathered to eat flesh and drink blood, filling themselves at the Lord's table with horses and chariots, mighty men, and all men of war. Isaiah and Joel add to the picture, describing the Lord mustering His host, the nations gathered for judgment in the valley of decision, and the sun, moon, and stars withdrawing their light as the Lord roars out of Zion.
So the Supper of the Great God stands as the terrible counterpart to the Marriage Supper of the Lamb: where the Bride of Christ celebrates in the fellowship and joy of Heaven, the birds and beasts of the earth are summoned to consume the flesh of those who made war against the Lamb and were destroyed by the sword of His mouth.
The scriptures
And I saw an angel standing in the sun; and he cried with a loud voice, saying to all the fowls that fly in the midst of heaven, Come and gather yourselves together unto the supper of the great God; That ye may eat the flesh of kings, and the flesh of captains, and the flesh of mighty men, and the flesh of horses, and of them that sit on them, and the flesh of all men, both free and bond, both small and great.
And I saw the beast, and the kings of the earth, and their armies, gathered together to make war against him that sat on the horse, and against his army. And the beast was taken, and with him the false prophet that wrought miracles before him, with which he deceived them that had received the mark of the beast, and them that worshipped his image. These both were cast alive into a lake of fire burning with brimstone. And the remnant were slain with the sword of him that sat upon the horse, which sword proceeded out of his mouth: and all the fowls were filled with their flesh.
Thou shalt fall upon the mountains of Israel, thou, and all thy bands, and the people that is with thee: I will give thee unto the ravenous birds of every sort, and to the beasts of the field to be devoured.
And, thou son of man, thus saith the Lord GOD; Speak unto every feathered fowl, and to every beast of the field, Assemble yourselves, and come; gather yourselves on every side to my sacrifice that I do sacrifice for you, even a great sacrifice upon the mountains of Israel, that ye may eat flesh, and drink blood. Ye shall eat the flesh of the mighty, and drink the blood of the princes of the earth, of rams, of lambs, and of goats, of bullocks, all of them fatlings of Bashan. And ye shall eat fat till ye be full, and drink blood till ye be drunken, of my sacrifice which I have sacrificed for you. Thus ye shall be filled at my table with horses and chariots, with mighty men, and with all men of war, saith the Lord GOD.
I have commanded my sanctified ones, I have also called my mighty ones for mine anger, even them that rejoice in my highness. The noise of a multitude in the mountains, like as of a great people; a tumultuous noise of the kingdoms of nations gathered together: the LORD of hosts mustereth the host of the battle. They come from a far country, from the end of heaven, even the LORD, and the weapons of his indignation, to destroy the whole land. Howl ye; for the day of the LORD is at hand; it shall come as a destruction from the Almighty. Therefore shall all hands be faint, and every man’s heart shall melt:
Proclaim ye this among the Gentiles; Prepare war, wake up the mighty men, let all the men of war draw near; let them come up: Beat your plowshares into swords, and your pruninghooks into spears: let the weak say, I am strong. Assemble yourselves, and come, all ye heathen, and gather yourselves together round about: thither cause thy mighty ones to come down, O LORD. Let the heathen be wakened, and come up to the valley of Jehoshaphat: for there will I sit to judge all the heathen round about. Put ye in the sickle, for the harvest is ripe: come, get you down; for the press is full, the fats overflow; for their wickedness is great. Multitudes, multitudes in the valley of decision: for the day of the LORD is near in the valley of decision. The sun and the moon shall be darkened, and the stars shall withdraw their shining. The LORD also shall roar out of Zion, and utter his voice from Jerusalem; and the heavens and the earth shall shake: but the LORD will be the hope of his people, and the strength of the children of Israel.
From the books
This answer is drawn from these passages in the Mary Banks Faith Library.