But the day of the Lord will come like a thief, and then the heavens will pass away with a roar, and the heavenly bodies will be burned up and dissolved, and the earth and the works that are done on it will be exposed. Since all these things are thus to be dissolved, what sort of people ought you to be in lives of holiness and godliness, waiting for and hastening the coming of the day of God, because of which the heavens will be set on fire and dissolved, and the heavenly bodies will melt as they burn! But according to his promise we are waiting for new heavens and a new earth in which righteousness dwells.
2 Peter 3:10-13
But the Day of the Lord will come. His longsuffering grace will not stay the reckoning time for ever. The metaphor of 'the thief in the night' does not suggest that it will come silently (as the following words make clear), but suddenly and without warning. As Christ Himself said it will be 'in such an hour as ye think not'. Peter's words here are awe-inspiring and speak of the tremendous trial by fire which shall overtake our world at the end: What we ought to pay particular heed to is the phrase 'the works that are therein'. As Paul says in 1 Corinthians 3 'the fire shall try every man's work' and although he is referring particularly to believers' works, it is clear that Peter's thought is wider and includes those of unbelievers also. In the light of this, Peter might well say, 'What manner of persons ought ye to be..?', for 'holy conversation and godliness' are the only things that will withstand the fire of God's judgment and emerge as constituent parts of the new heavens and new earth. It is all a question of having an eye to the future, the eternal future. If we really believed that such a visitation as this will come upon the world we would be supremely occupied in seeing that that day should not overtake us unawares but find us living holy and spotless lives. In this, as in other matters, the fear of the Lord is the beginning of wisdom!