There is nothing yet unfulfilled before he returns. It could be today.
Nope
There is the Rev 16 seven last plagues that have not happened yet -- that must happen before the Rev 19 second coming event will take place.
And there is the Rev 13-14 issue of the mark of the beast that has not happened yet - before the second coming event also described at the end of Rev 14 ... and also in Rev 19.
You will never see it in a million years if you are waiting for the symbol to appear. .
God is literal in the book of Revelation, the saints are literal, the devill is literal, the wicked are literal , the Earth is usually literal...
Just because "a symbol is ever used" in a given book - does not give one license to spiritualize everything in the book into oblivion.
So then Revelation 16
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Then I heard a loud voice from {the temple}(lit), saying to {the seven angels} (lit), “Go and pour out on the earth the seven bowls of the {wrath of God} (lit).”
2 So the first
angel went and poured out his bowl on {the earth}(lit); and it became a {loathsome and malignant sore on the people}(lit) who had the mark of the beast and {who worshiped}(lit) his image.
3 The {second
angel}(lit) poured out his bowl into the {sea, and it became blood like}(it) LIKE
that of a dead man; and {every living soul in the sea died}(lit).
4 Then the third
angel poured out his bowl into the {rivers and the springs of waters; and they became blood}(lit). 5 And I heard the angel of the waters saying, {“Righteous are You, who are and who were, O Holy One, because You judged these things; 6 for they poured out the blood of saints and prophets, and You have given them blood to drink. They deserve it.”} (lit) 7 And I heard the altar saying,{ “Yes, O Lord God, the Almighty, true and righteous are Your judgments.”}(lit)
8 The fourth
angel poured out his bowl upon {the sun, and it was given to it to scorch men with fire}(lit). 9 {Men were scorched with fierce heat; and they blasphemed the name of God who has the power over these plagues, and they did not repent so as to give Him glory.}(lit)
10 Then the fifth
angel poured out his bowl on the throne of the beast, and his kingdom became darkened; and {they gnawed their tongues because of pain, 11 and they blasphemed the God of heaven because of their pains and their sores; and they did not repent of their deeds.}(lit)
12 The sixth
angel poured out his bowl on the great river, the Euphrates; and its water was dried up, so that the way would be prepared for the kings from the east.
Armageddon
13 And I saw
coming out of the mouth of the dragon and out of the mouth of the beast and out of the mouth of the false prophet, three unclean spirits like frogs; 14 for {they are spirits of demons, performing signs, which go out to the kings of the whole world, to gather them together for the war of the great day of God, the Almighty.}(lit) 15 (“Behold, I am coming like a thief. Blessed is the one who stays awake and keeps his clothes, so that he will not walk about naked and men will not see his shame.”) 16 And they gathered them together to the place which in Hebrew is called Har-Magedon.
Seventh Bowl of Wrath
17 Then the seventh
angel poured out his bowl upon the air, and a loud voice came out of the temple from the throne, saying, “It is done.” 18 And there were flashes of lightning and sounds and peals of thunder; and {there was a great earthquake, such as there had not been since man came to be upon the earth, so great an earthquake
was it, and so mighty. 19 The great city was split into three parts, and the cities of the nations fell}(lit). Babylon the great was remembered before God, to give her the cup of the wine of His fierce wrath. 20 And {every island fled away, and the mountains were not found. 21 And huge hailstones, about one hundred pounds each, *came down from heaven upon men; and men blasphemed God because of the plague of the hail, because its plague *was extremely severe.} (lit-literal)
