“their dominion was taken away.” This verse refers to the dominion of the demons who serve Satan—the demons’ dominion will be taken away. The demons who serve Satan will be defeated in the Battle of Armageddon (Rev. 19:11-21) and thrown into the Abyss along with Satan. They will be there in prison during the 1,000-year reign of Christ on earth (Rev. 20:1-3). Revelation 20:1-3 does not mention Satan’s demons—it focuses on the leader, Satan—but the scope of Scripture along with verses such as Daniel 7:12 and Isaiah 24:21-22 show us that the demons are also imprisoned with Satan. They are imprisoned in a god-prison technically referred to as “Tartarus” in 2 Peter 2:4, but also called “prison” in 1 Pet. 3:19, “the Abyss” in Revelation 20:1, and the “pit” in Isaiah 24:22.
God could have thrown the demons into the Lake of Fire immediately after the Battle of Armageddon, but instead he had them imprisoned with Satan during the 1,000-year Millennial Kingdom, and this is why the text says these demons “were granted an extension of their lives for a season and a time” (see commentary on Rev. 20:7). At the end of the 1,000 years, Satan and his demons will be released, and the demons will help Satan gather an army to fight against God’s people. But Satan and his demonic army will be defeated in the Final War of Revelation 20:9-10, and then they will be thrown into the Lake of Fire (Rev. 20:7-10) (see commentary on Isa. 24:21).
The “beasts” that will be imprisoned and thus granted an extension of their lives are the demons behind the scenes controlling the kingdoms of the earth. As Daniel’s vision opens in Daniel 7:3, there are “beasts,” kingdoms, that come out of the “sea” (the “sea” is the masses of Gentile people; cp. Rev. 17:2). But those kingdoms did not arise spontaneously, there were four spirits that stirred up and influenced the rise of those kingdoms, and they would have had help from other demons as well. However, in Daniel 7:12, the “beasts” are not kingdoms or earthly kings, but are the demons who were behind the scenes influencing what happened in the kingdoms. The “beasts” of Daniel 7:12 cannot be earthly kings or earthly kingdoms because all earthly kingdoms are destroyed by the Messiah at Armageddon (Dan. 2:34-35, 44) and all earthly kings and armies are killed in that battle (Rev. 19:19-21). After the Battle of Armageddon, Jesus Christ will rule over the whole earth (cp. Ps. 2:8; 72:8-11; Dan. 2:35; 7:14; Micah 5:4; Zech. 9:10), and the Antichrist and satanic systems on earth will be destroyed (2 Thess. 2:8; Rev. 19:20). No evil or satanic “kingdom” or “nation” will be on earth during the Millennial kingdom, and “kingdom” cannot be imprisoned, so the fact that these “beasts” will be granted an extension of life during that time shows that they are demons. Demons will be imprisoned in Tartarus during the 1,000-year reign of Christ on earth.
[For more on Tartarus, see commentary on 2 Peter 2:4. For more on the demonic army, see commentary on Isa. 24:21. For a better understanding of the chronology of the End Times, see commentary on Matt. 25:32, “as a shepherd separates the sheep from the goats”].