So what about those 8 beast kings mentioned in Revelation 17??? It's not about Trump, nor Obama, nor Biden, etc. It's about a coming false one to Jerusalem that will claim to be a son of David of the tribe of Judah.
Rev.13 revealed the idea of two types of beasts. A beast kingdom, and a beast entity, or person. It follows Daniel 4, which compares Nebuchadnezzar as a beast punished by God with Neb living like a wild beast, and then the four great beast kingdoms prophecy in Daniel 7.
Below in Rev.17, both the idea of a beast kingdom, and beast kings are given.
Rev 17:8-14
8 The beast that thou sawest was, and is not; and shall ascend out of the bottomless pit, and go into perdition: and they that dwell on the earth shall wonder, whose names were not written in the book of life from the foundation of the world, when they behold the beast that was, and is not, and yet is.
Thinking cap on: who is it that is already been judged and sentenced to perdition? That above "beast" we are told goes into perdition, i.e., perishes. As of today, the only one already judged and sentenced to perish is Satan and his angels. No flesh man is judged and sentenced to perish yet, for that only happens with God's future Great White Throne Judgment. So by this, Lord Jesus revealed this beast here is about Satan himself.
Satan "was", meaning he once setup a beast kingdom that had 7 crowns, back in the old world when he first rebelled in coveting God's throne, and then drew a third of the angels with him (Revelation 12:3-4).
Satan "and is not", because God destroyed Satan's little original beast kingdom back then. Jesus said He saw Satan as lightning fall from heaven (Luke 10:18).
Satan "shall ascend out of the bottomless pit, and go into perdition". When? Jesus is getting ready here in Rev.17 to reveal it.
Who will know about this, that it's Satan as that beast king? Those who's names are written in the book of life from the foundation of the world. All others will 'wonder' at that beast, not knowing who he really is.
9 And here is the mind which hath wisdom. The seven heads are seven mountains, on which the woman sitteth.
That's a subject break from the idea of the beast kings. That "seven heads" is about the beast kingdom idea in Rev.13:1-2. The seven heads represents 7 geographical areas on earth. Don't listen to men's pop ideas that say this is about seven hills. The previous existing seven heads of the Rev.12:3-4 beast kingdom of old when Satan drew a third of the stars in rebellion, where was that seven heads, or mountains? Places on earth that Satan then ruled over, of course.
10 And there are seven kings: five are fallen, and one is, and the other is not yet come; and when he cometh, he must continue a short space.
Five of the seven beast kings are past history. One existed in John's day (Domitian, a 6th). And the 7th was yet to come. The 7th beast king is still yet to come today; that will be the pseudochristos that Jesus warned of in Jerusalem for the end (Matthew 24:23-26).
Lord Jesus gave us another hint in the above verse. He said that 7th beast king, when he comes, "must continue a short space". That idea links with Revelation 12:7 forward about Satan being booted out of Heaven down to this earth for the very end, as we are told he then knows he has but a 'short time'. That short time, or short space, is pointing to the shortened time of the "great tribulation" Lord Jesus warned us about.
11 And the beast that was, and is not, even he is the eighth, and is of the seven, and goeth into perdition.
The beast king that "was" (Satan), and "is not" (Satan's old beast kingdom ended by God), "and is of the seven" (Satan was over the previous beast kings, part of his work), and he (Satan) goes into perdition (at the end of Christ's future "thousand years" reign per Revelation 20:9 forward. Thus Satan will be the 8th beast king once he is loosed from his pit prison at the end of Christ's future millennial reign, and he will go tempt the nations of unsaved after they have been shown the Truth by Christ and His elect during the "thousand years".
12 And the ten horns which thou sawest are ten kings, which have received no kingdom as yet; but receive power as kings one hour with the beast.
These ten horn kings are separate from the previous mention of beast kings. These ten horn kings reign concurrently WITH Satan (7th beast king) when he comes. That "one hour" is another anchor marker from Lord Jesus. Remember the parable of the laborers in the field, how some worked only "one hour" and got the same pay as those who worked all day? In the ten virgin's parable, the Bridegroom appears at midnight. Thus the ten virgins fall asleep during the 11th hour (symbolic of the "one hour", or last hour, i.e., the "great tribulation" time).
13 These have one mind, and shall give their power and strength unto the beast.
The ten horn kings will be under Satan as the 7th beast king. Per Daniel 7, a "little horn" comes up among the ten horns, and subdues three of the kings. Satan is that "little horn", that's another one of his many titles in Scripture.
14 These shall make war with the Lamb, and the Lamb shall overcome them: for He is Lord of lords, and King of kings: and they that are with Him are called, and chosen, and faithful.
KJV
That's about the battle of Armageddon on the "day of the Lord" when Lord Jesus returns to gather His Church and begin reign over all nations.
