Expositor's Bible Commentary Commentary 2 Peter 3:7

"but the heavens that now are, and the earth, by the same word have been stored up for fire, being reserved against the day of judgment and destruction of ungodly men." — 2 Peter 3:7 (ASV)

Peter’s reference to a future conflagration to destroy the present cosmos is highly unusual. The OT speaks of fire in the day of the Lord (Psalms 97:3; Isaiah 66:15– 16; Daniel 7:9–10; Micah 1:4; Malachi 4:1). And Mt 3:11–12 speaks of the future baptism of fire by the Messiah in which he will destroy the “chaff” (cf. 2 Thessalonians 1:7). Peter argues that just as in the past God purged the then-existing world by his word and by waters, so in the future he will purge the world by his word and by fire. Whether this will take place before the Millennium or after, Peter does not say. Matthew 3:11–12 supports the former, while the sequence of Rev 20-21 puts the new heaven and new earth after the thousand years (cf. 2 Peter 3:13).