2 Peter 3:5-7

But they (scoffers) deliberately forget that long ago by God's word the heavens came into being and the earth was formed out of water and by water. By these waters also the world of that time was deluged and destroyed. By the same word the present heavens and earth are reserved for fire, being kept for the day of judgment and destruction of the ungodly. 

But since they deliberately forget that long ago by God's word 
Genesis 1:6  And God said, "Let there be a vault between the waters to separate water from water."
Genesis 1:9  And God said, "Let the water under the sky be gathered to one place, and let dry ground appear." And it was so. 
Hebrews 11:3  By faith we understand that the universe was formed at God's command, so that what is seen was not made out of what was visible.

the heavens came into being and the earth was formed out of water and by water 
Psalm 24:1-2  The earth is the LORD's and everything in it, the world and all who live in it; for he founded it on the seas and established it on the waters.

By these waters also the world at that time 
2 Peter 2:5  ...if he did not spare the ancient world when he brought the flood on its ungodly people, but protected Noah, a preacher of righteousness, and seven others; ...

was deluged and destroyed 
Genesis 7:21-22  Every living thing that moved on land perished--birds, livestock, wild animals, all the creatures that swarm over the earth, and all mankind. Everything on dry land that had the breath of life in its nostrils died.

By the same word the present heavens and earth are reserved for fire 
2 Peter 3:10  But the day of the Lord will come like a thief. The heavens will disappear with a roar; the elements will be destroyed by fire, and the earth and everything done in it will be laid bare.
2 Peter 3:12b  That day will bring about the destruction of the heavens by fire, and the elements will melt in the heat.
2 Thessalonians 1:7b  This will happen when the Lord Jesus is revealed from heaven in blazing fire with his powerful angels.

being kept for the day of judgment and destruction of the ungodly 
Matthew 10:15  "Truly I tell you, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town."
2 Peter 2:9  ... if this is so, then the Lord knows how to rescue the godly from trials and hold the unrighteous for punishment on the day of judgment.

(parentheses are mine)

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