The Thesis:  ¹ Beloved, I now write to you this second epistle (in both of which I stir up your pure minds by way of reminder), ²  that you may be mindful of the words which were spoken before by the holy prophets, and of the commandment of us, the apostles of the Lord and Savior,

A  ³ knowing this first: that scoffers will come in the last days, walking according to their own lusts, ⁴ and saying, “Where is the promise of His coming? For since the fathers fell asleep, all things continue as they were from the beginning of creation.” ⁵ For this they willfully forget: that by the word of God the heavens were of old, and the earth standing out of water and in the water, ⁶ by which the world that then existed perished, being flooded with water. ⁷ But the heavens and the earth which are now preserved by the same word, are reserved for fire until the day of judgment and perdition of ungodly men.

B  ⁸ But, beloved, do not forget this one thing, that with the Lord one day is as a thousand years, and a thousand years as one day. ⁹  The Lord is not slack concerning His promise, as some count slackness, but is longsuffering toward us, not willing that any should perish but that all should come to repentance.

A’  ¹⁰ But the day of the Lord will come as a thief in the night, in which the heavens will pass away with a great noise, and the elements will melt with fervent heat; both the earth and the works that are in it will be burned up. ¹¹ Therefore, since all these things will be dissolved,

B’  what manner of persons ought you to be in holy conduct and godliness, ¹² looking for and hastening the coming of the day of God,

A’  because of which the heavens will be dissolved, being on fire, and the elements will melt with fervent heat?

B’ ¹³ Nevertheless we, according to His promise, look for new heavens and a new earth in which righteousness dwells.

The Theme Core of the Entire Book of 2^nd Peter
The Thesis:  Reminder to be Mindful of all that is said in the Scriptures.
A: Judgment and Fall of the Unsaved (“them”).
B:  Presence with Jesus for the Saved (“us”).