“Fire,” as one of the Bible’s themes, appears in a number of contexts:
First, fire is symbolic of God’s presence, in that it is ethereal but visible in its effect, warming, comforting and cheering, mysterious in the way it works, and terrible in its consuming power. Deuteronomy 4:24; 9:3 Isaiah 33:14 Hebrews 12:25-29 In Exodus 3:2, the fire didn’t consume the bush, and in Exodus 14:19-20, the pillar of fire didn’t consume the Israelites.
Second, fire, or heat from fire, symbolizes a purifying agent. Proverbs 25:4-5 Isaiah 1:25 Isaiah 4:4 Malachi 3:2-3 Isaiah 6:6-7 Ezekiel 22:18-19 Genesis 19:24 Luke 17:29 Jeremiah 6:27-30 Numbers 11:1-32 Kings 1:10-12 Amos 4:7 Exodus 9:23-24 Psalms 18:13 Isaiah 9:19 Ezekiel 38:22 Revelation 8:7-8
Christ-followers don’t have to worry about most of those things, and can even look forward to the fire of God’s presence in his Holy Spirit. But if you don’t want to be “on fire” for the Lord, you’d best check your spiritual condition closely, lest you are in the Laodicean condition.