Fire was considered by certain of the ancient pantheistic philosophers to have been the primeval element out of which all things had evolved, and this same myth is promulgated today by evolutionary cosmogonists in the form of their "Big Bang" theory. The fact is, however, that fire is a creation of God used both actually and symbolically as God's vehicle of judgment on sin.
It is significant that both the first and last references to fire in the Bible mention both fire and brimstone, used in flaming judgment on human rebellion against God. First, "the LORD rained upon Sodom and upon Gomorrah brimstone and fire from the LORD out of heaven" (Genesis 19:24). And finally, "the fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone: which is the second death" (Revelation 21:8).
Today's verse is a reference to Moses' words to the tribes as they were preparing to enter the promised land after his death. Warning them against corrupting their faith through idolatry, he said: "For the LORD thy God is a consuming fire, even a jealous God" (Deuteronomy 4:24). Its New Testament context is a grave warning against rejecting God's Word: "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" (Hebrews 12:25).
In a sense, God's Word is also God's fire. "His word was in mine heart as a burning fire shut up in my bones, and I was weary with forbearing, and I could not stay" (Jeremiah 20:9). It is better to be refined with the fire of God's Word than to be consumed by His judgment fire. HMM