Brethren in Christ:
Here's some more Bible info about God's consuming fire on the coming last day of this present world, on the "day of the Lord"...
Heb 12:25-29
25 See that ye refuse not Him That speaketh. For if they escaped not who refused Him That spake on earth, much more shall not we escape, if we turn away from Him That speaketh from heaven:
26 Whose voice then shook the earth: but now He hath promised, saying, "Yet once more I shake not the earth only, but also heaven."
Very simple, Paul shows that God at one time before "shook the earth", so when was that? It was at Satan's overthrow, when Satan first rebelled against God. There's nothing written during the time of Noah about God shaking this earth back then.
But Paul then shows that, "Yet once more..." God is going to shake not only the earth, but Heaven also. When is that for? It is for the final day of this present world, on the "day of the Lord".
Remember that point about BOTH heaven and earth shaking for the end of this world.
27 And this word, "Yet once more", signifieth the removing of those things that are shaken, as of things that are made, that those things which cannot be shaken may remain.
By that Paul defined just to what level... of shaking in that old world it was, and is comparing it to this coming final shaking of the earth, and Heaven in our near future. Jeremiah 4:23-26 refers to the mountains and all the hills having trembled at that first shaking of the earth.
28 Wherefore we receiving a kingdom which cannot be moved, let us have grace, whereby we may serve God acceptably with reverence and godly fear:
29 For our God is a consuming fire.
KJV
Paul links God's consuming fire event with this next shaking of heaven and the earth that is coming at the end of this present world, on the "day of the Lord". Peter also showed this in 2 Peter 3:10 for the end of this present world, with God's consuming fire burning man's works off this earth. Did you know brethren that fire from God is also going to 'test' our own works in Christ?
1 Cor 3:10-15
10 According to the grace of God which is given unto me, as a wise masterbuilder, I have laid the foundation, and another buildeth thereon. But let every man take heed how he buildeth thereupon.
11 For other foundation can no man lay than that is laid, which is Jesus Christ.
Is your foundation in Christ Jesus, laid on His foundation?
12 Now if any man build upon this foundation gold, silver, precious stones, wood, hay, stubble;
13 Every man's work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man's work of what sort it is.
On that final day of this world, all our works are going to be tried by God's fire, to see what kind of work it is.
14 If any man's work abide which he hath built thereupon, he shall receive a reward.
15 If any man's work shall be burned, he shall suffer loss: but he himself shall be saved; yet so as by fire.
KJV
Thus God's consuming fire on the "day of the Lord" is not just to burn earth matter, it is going to burn man's works, even deeds not accepted by Christ on that day. No evil will escape God's fire on that day. Might this have something to do with Paul showing Heaven being shaken also on that day?
Isa 13:9-13
9 Behold, the day of the LORD cometh, cruel both with wrath and fierce anger, to lay the land desolate: and He shall destroy the sinners thereof out of it.
10 For the stars of heaven and the constellations thereof shall not give their light: the sun shall be darkened in his going forth, and the moon shall not cause her light to shine.
11 And I will punish the world for their evil, and the wicked for their iniquity; and I will cause the arrogancy of the proud to cease, and will lay low the haughtiness of the terrible.
12 I will make a man more precious than fine gold; even a man than the golden wedge of Ophir.
13 Therefore I will shake the heavens, and the earth shall remove out of her place, in the wrath of the LORD of hosts, and in the day of His fierce anger.
KJV
That's the event Apostle Paul was pointing to in Hebrews 12:25-29 involving God's consuming fire!
Here's another example of that future shaking of the heavens and the earth on that "day of the Lord"...
Joel 3:10-17
10 Beat your plowshares into swords, and your pruninghooks into spears: let the weak say, I am strong.
11 Assemble yourselves, and come, all ye heathen, and gather yourselves together round about: thither cause thy mighty ones to come down, O LORD.
12 Let the heathen be wakened, and come up to the valley of Jehoshaphat: for there will I sit to judge all the heathen round about.
The "valley of Jehoshaphat" is an area between Jerusalem and the Mount of Olives. This is where God will gather those nations for the end that come up against Jerusalem on the last day of this world. They will be burned up, with a remnant of them leftover per Zechariah 14.
13 Put ye in the sickle, for the harvest is ripe: come, get you down; for the press is full, the fats overflow; for their wickedness is great.
14 Multitudes, multitudes in the valley of decision: for the day of the LORD is near in the valley of decision.
Recall how Revelation 14 refers to this harvest sickle. Also see Matthew 13:39 about that harvest time for the end of this world.
15 The sun and the moon shall be darkened, and the stars shall withdraw their shining.
16 The LORD also shall roar out of Zion, and utter His voice from Jerusalem; and the heavens and the earth shall shake: but the LORD will be the hope of his people, and the strength of the children of Israel.
17 So shall ye know that I am the LORD your God dwelling in Zion, My holy mountain: then shall Jerusalem be holy, and there shall no strangers pass through her any more.
KJV
There's that idea of His shaking the heavens and the earth linked again with the day of His coming on "the day of the Lord".
So really, we don't have to rely only on the New Testament Scriptures that Lord Jesus and His Apostles showed us about His future return on the "day of the Lord", because the Old Testament prophets testified of that same event too, and that is where the New Testament teaching originated from. It's been a Bible prophecy from long ago all along.