The expression is only used in Revelation, but the imagery is not new. The book of Revelation is so full of imagery, symbolism, metaphors, and hyperbole that originated from the same symbolism of the OT prophesies. It is truly not possible to understand Revelation without first studying the OT prophesies. The word translated in English as "fire" is Strong's Gr. 4442, "πῦρ", or pur.(1) It became the imagery of God's judgment. Fire from heaven was the judgment God poured out upon sinful men, and sinful nations.
"...Lest My fury go out as fire, and hath burned, And there is none quenching, Because of the evil of your doings." (Jer. 4:4, YLT)
"...Lest My fury go forth as fire, And hath burned, and none is quenching, Because of the evil of your doings." (Jer. 21:12, YLT)
"And I have set My jealousy against thee, And they have dealt with thee in fury, Thy nose and thine ears they turn aside, And thy posterity by sword falleth, They, thy sons and thy daughters do take away, And thy posterity is devoured by fire." (Ezek. 23:25, YLT)
"3 He hath cut off in the heat of anger every horn of Israel, He hath turned backward His right hand From the face of the enemy, And He burneth against Jacob as a flaming fire, It hath devoured round about.
4 He hath trodden His bow as an enemy, Stood hath His right hand as an adversary, And He slayeth all the desirable ones of the eye, In the tent of the daughter of Zion, He hath poured out as fire His fury." (Lam. 2:3-4, YLT)
The words "as a" and "as" are indicators of metaphors and similes, where one thing is used to visualize another, or represent an equal state. God's fury is fire; an equivalent statement- fury = fire. His judgment was poured out like fire. The word "like" is another indicator of a comparison, of a metaphor or simile.
Fire is the imagery that we can all visualize from the destruction of Sodom and Gomorrah which was literally fire from heaven. The destruction of Sodom and Gomorrah forever represented the anger and fury of God against the evil ones who refused to repent. That burning destruction (Gen. 18:20-19:28) was visible in the smoke and fire that lingered from those cities, and became indelibly imprinted upon the minds of mankind. So, thereafter the use of the word fire in His prophetic language became the symbol of God's judgment, just as the use of the word "flood" called to mind God's judgment against wicked men.
Most probably the "lake of fire" originates from the funeral pyre imagery of the valley of the sons of Hinnom, or Gehenna as related of the valley of Topheth in 2 Kings 23:10....
"And he hath defiled Topheth, that [is] in the valley of the son of Hinnom, so that no man doth cause his son and his daughter to pass over through fire to Molech." (YLT)
where the children were being sacrificed. Topheth was the sounds of the drums used to drown out the screams of the children being burned alive. This is the imagery that is recalled in Revelation by the lake of fire. It is the judgment God poured out upon the evil ones. And, His judgment, or fire filled the entire valley.
So whenever we read of God's fury as fire in the prophesies we can almost always substitute the word "judgment" as follows:
"...but [judgment] came down from heaven..." (Rev. 20:9)
"into the lake of [judgment]...." (Rev. 20:10)
A lake is a valley that is usually filled with water. But, in Revelation the imagery is one that is filled with the fire of God's judgment. What is eternal is the burning fire, or the continual judgment of God. It is too tempting to try to force all of the metaphors of God's prophesies into literal physical earthly conditions because that is how men relate to the imagery. What we can see, touch, smell, and feel is our carnal realm, and God uses that to help us picture His spiritual nature.
If you are interested, I explore more of this imagery in the post "The Lake of Fire" at my blog ShreddingTheVeil.
- Strong's Gr. 4442, pur - Biblehub