Revelation 20:14

Then Death and Hades were cast into the lake of fire
Death (representing the bodies of the dead which had lain in the earth and sea) and Hades (the place of torment for soul and spirit of the unrighteous dead between death and the judgment) will be destroyed. Their physical reality vanishes in the fleeing of the earth and heaven—the destruction of the old order:

Death and Hades, here viewed as if they were personal beings, share the same fate. They, of course, cease to be. There is nothing more of temporal death or of the place of departed spirits after this. They are not personal beings, hence their casting into “the lake of fire” is the end of them; but, conceived of as persons, they are consigned to exactly the same eternal punishment with the other wicked.1

They are the final enemies to be destroyed before the eternal state and are vanquished to the Lake of Fire, a cosmic garbage dump:

The clearest and most vivid of the New Testament terms used to describe the final hell, the lake of fire, is geenna (Gehenna). Gehenna is the New Testament word for the valley of Ben-Hinnom (also called Topheth; 2K. 2K. 23:10; Isa. Isa. 30:33; Jer. Jer. 7:31-32; Jer. 19:6), located southwest of Jerusalem. In Old Testament times, idolatrous Israelites burned their children in the fire there as sacrifices to false gods (Jer. Jer. 19:2-6). In Jesus’ day, it was the site of Jerusalem’s garbage dump. The fires kept constantly burning there gave off foul-smelling smoke, and the dump was infested with maggots. Sometimes the bodies of criminals were dumped there. The valley of Ben-Hinnom was thus an apt picture of eternal hell, one used repeatedly by Jesus (Mtt. Mat. 5:22, Mat. 5:29, Mat. 5:30; Mat. 10:28; Mat. 18:9; Mat. 23:15, Mat. 23:33; Mark Mark 9:43, Mark 9:45, Mark 9:47; Luke Luke 12:5). Hell will be God’s eternal cosmic dump; its inmates will be burning as garbage forever.2

Their casting into the Lake of Fire may be another indicator that none who stand in this judgment are saved. All who were part of the second resurrection (which emptied Death and Hades) are bound for the Lake of Fire.

This is the fulfillment of the promises of God to destroy death and the grave:

He will swallow up death forever, And the Lord GOD will wipe away tears from all faces; the rebuke of His people He will take away from all the earth; for the LORD has spoken. (Isa. Isa. 25:8)

So when this corruptible has put on incorruption, and this mortal has put on immortality, then shall be brought to pass the saying that is written: “Death is swallowed up in victory. O Death, where is your sting? O Hades, where is your victory?” (1Cor. 1Cor. 15:54-55 cf. Hos. Hos. 13:14).)

Then comes the end, when He delivers the kingdom to God the Father, when He puts an end to all rule and all authority and power. For He must reign till He has put all enemies under His feet. The last enemy that will be destroyed is death. (1Cor. 1Cor. 15:24-26)

And God will wipe away every tear from their eyes; there shall be no more death, nor sorrow, nor crying. There shall be no more pain, for the former things have passed away. (Rev. Rev. 21:4+)

This is the second death
The MT and NU texts have: “This is the second death, the lake of fire.” Those who overcome by placing their faith in the Overcomer “shall not be hurt by the second death” (Rev. Rev. 2:11+): Those who participated in the first resurrection need not fear the second death. “Over such the second death has no power” (Rev. Rev. 10:6+).

He who overcomes shall inherit all things, and I will be his God and he shall be My son. But the cowardly, unbelieving, abominable, murderers, sexually immoral, sorcerers, idolaters, and all liars shall have their part in the lake which burns with fire and brimstone, which is the second death. (Rev. Rev. 21:7-8+)

See Births, Deaths, and Resurrections.

Notes

1 J. A. Seiss, The Apocalypse: Lectures on the Book of Revelation (Grand Rapids, MI: Zondervan Publishing House, 1966), 481.

2 John MacArthur, Revelation 12-22 : The MacArthur New Testament Commentary (Chicago, IL: Moody Press, 2000), Rev. 20:14.

Read Revelation 20:14