How does Michael cast the Dragon out of heaven? I'm not asking whether or not he did, I'm asking how he did. And what does it mean that Michael and his angels cast the Dragon and his angels out of heaven? Where is the heaven in which were the Dragon and his angels?
Consider these verses. The kingdom of heaven was a violent place:
"And from the days of John the Baptist until now the kingdom of heaven [of God] suffereth violence, and the violent take it by force." -- Matt 11:12
. . . and was controlled by the Jewish leadership:
"Therefore say I unto you, The kingdom of God [of Heaven] shall be taken from you [chief priests and elders,] and given to a nation bringing forth the fruits thereof." -- Matt 21:43
. . . who were children of Satan:
"Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it." -- John 8:44
"And say, If we had been in the days of our fathers, we would not have been partakers with them in the blood of the prophets. Wherefore ye be witnesses unto yourselves, that ye are the children of them which killed the prophets. Fill ye up then the measure of your fathers. Ye serpents, ye generation of vipers, how can ye escape the damnation of hell?" -- Matt 23:30-33
So, the kingdom of heaven, from the days of John the Baptist, was controlled by the violent Jewish leadership, who were also the children of Satan. But when Christ was resurrected, the kingdom went to him and his children; and that transfer occurred shortly after his resurrection, but before his ascension. We know this because Jesus ate and drank with his disciples in the kingdom of heaven.:
"Verily I say unto you, I will drink no more of the fruit of the vine, until that day that I drink it new in the kingdom of God." -- Mark 14:25
"And he said unto them, With desire I have desired to eat this passover with you before I suffer: For I say unto you, I will not any more eat thereof, until it be fulfilled in the kingdom of God." -- Luke 22:15-16
"And it came to pass, as he sat at meat with them, he took bread, and blessed it, and brake, and gave to them." -- Luke 24:30
"And while they yet believed not for joy, and wondered, he said unto them, Have ye here any meat? And they gave him a piece of a broiled fish, and of an honeycomb. And he took it, and did eat before them." -- Luke 24:41-43
"And we are witnesses of all things which he did both in the land of the Jews, and in Jerusalem; whom they slew and hanged on a tree: Him God raised up the third day, and shewed him openly; Not to all the people, but unto witnesses chosen before God, even to us, who did eat and drink with him after he rose from the dead." -- Acts 10:39-41
Therefore, Jesus ate with his disciples in the kingdom of God [kingdom of heaven,] after his resurrection, but before his ascension. And from that time forward, Jesus reigned over the heaven and the earth:
"And Jesus came and spake unto them, saying, All power is given unto me in heaven and in earth." -- Matt 28:18
Now, Satan was not the least bit happy, because once Christ rose from the dead, the kingdom transferred from his (Satan's) children, to the children of God:
"And she brought forth a man child, who was to rule all nations with a rod of iron: and her child was caught up unto God, and to his throne." -- Rev 12:5 KJV
"Woe to the inhabiters of the earth and of the sea! for the devil is come down unto you, having great wrath, because he knoweth that he hath but a short time." -- Rev 12:12 KJV
While he still had some power, he tried to destroy the heirs to the kingdom:
"And the dragon was wroth with the woman, and went to make war with the remnant of her seed, which keep the commandments of God, and have the testimony of Jesus Christ." -- Rev 12:17 KJV
But, as soon as Satan's children were destroyed in the destruction of Jerusalem, he was powerless to prevent his imprisonment:
"And the light of a candle shall shine no more at all in thee [Babylon the Great, a.k.a., Jerusalem;] and the voice of the bridegroom and of the bride shall be heard no more at all in thee: for thy merchants were the great men of the earth; for by thy sorceries were all nations deceived." -- Rev 18:23
"And I saw an angel come down from heaven, having the key of the bottomless pit and a great chain in his hand. And he laid hold on the dragon, that old serpent, which is the Devil, and Satan, and bound him a thousand years, And cast him into the bottomless pit, and shut him up, and set a seal upon him, that he should deceive the nations no more, till the thousand years should be fulfilled: and after that he must be loosed a little season." -- Rev 20:1-3
Satan was only bound--not destroyed--because, unfortunately for the world, not all of his children were destroyed at that time. They and their seed have caused misery and havoc until this day.
One other point: Jesus said that the kingdom of God would be taken from the Jewish leadership and given to a nation. I believe it to be the following nation, which were the earliest Christians:
"But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light;" -- 1Pet 2:9
The remnant of the children of Israel--the early Church--received that promise from the Lord for keeping the covenant, and hearing the words of Christ; in other words, for keeping the faith:
"And now if ye will indeed hear my voice, and keep my covenant, ye shall be to me a peculiar people above all nations; for the whole earth is mine. And ye shall be to me a royal priesthood and a holy nation: these words shalt thou speak to the children of Israel." -- Exo 19:5-6 LXX
That is my interpretation.