John Gill emphasizes the significance of 2 Peter 3:7, explaining that the current heavens and earth are preserved by God's word, awaiting a future judgment by fire. He contrasts this preservation with the past destruction by water, highlighting that the world is being prepared for a final conflagration as a consequence of human sin. Gill notes that the natural world shows signs of this impending judgment through various fiery phenomena. He stresses the certainty of God's judgment, which will be universal and eternal, leading to the destruction of the ungodly. The sermon serves as a reminder of the seriousness of sin and the reality of divine judgment.