A little, five-word sentence—"You will not surely die"—was Satan the Devil's opening salvo to convince Adam and Eve that they could disregard the commands of God without consequence. It is evident from Eve's reply to his initial question that she understood both God's decree and His reasons for not wanting them to eat of the Tree of the Knowledge of Good and Evil. It was the reason, "lest you die," that Satan pounced on with his famous lying contradiction.
What most people do not realize is that Satan has been repeating this mantra ever since, and the vast majority of humanity has bought into it just as readily as our first parents in the Garden. The essence of Satan's lie is, "Go ahead and live as you like. There are no fatal consequences to your actions because you are already immortal." Theologically, this belief is called the doctrine of the immortality of the soul, and most Christian churches, both in America and abroad, teach it.
The Bible, however, does not support it.
Even as early as Genesis 2, God tells us that humans can die, and the underlying suggestion is that death can be permanent: "Of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die" (verse 17). An even clearer set of scriptures is found in Ezekiel 18. God says, "Behold, all souls are Mine; the soul of the father as well as the soul of the son is Mine; the soul who sins shall die" (verse 4). Just in case we fail to understand, He repeats Himself in verse 20.
We need to understand this. God says that the wages of sin—that is, what we earn as a result of our ungodly choices in life—is death (Romans 6:23). Yes, this means that we will lose our physical lives. But what about that spiritual component in us, the one Job called the "spirit in man" (Job 32:8)? When we die, says Solomon, it "return[s] to God who gave it" (Ecclesiastes 12:7). But what then?
Jesus says, "Whoever eats My flesh and drinks My blood has eternal life, and I will raise him up at the last day" (John 6:54). But what if a person refuses to sign on to His New Covenant? What happens to the unbeliever and the rebel? He says, "'Cast the unprofitable servant into the outer darkness. There will be weeping and gnashing of teeth. . . . Depart from Me, you cursed, into the everlasting fire prepared for the devil and his angels.' . . . And these will go away into everlasting punishment, but the righteous into eternal life" (verses Matthew 25:30, 41, 46).
Notice the difference in His two judgments: The "unprofitable servant," the "cursed," the unrepentant sinner, is thrown into "outer darkness," "everlasting fire," and "everlasting punishment," while the righteous enjoy eternal life. The reward of the saved and the fate of the wicked cannot both be eternal life, meaning that the "everlasting punishment" of the wicked must be eternal death, not eternal life in torment. Otherwise, God cannot be said to be just.
Jude makes an interesting comment in verse 7 of his epistle: "Sodom and Gomorrah . . . are set forth as an example, suffering the vengeance of eternal fire." The eternal fire that consumed those cities and their people is no longer burning, but its results are eternally valid: Those of Sodom and Gomorrah are still dead! Thus, eternal fire or "everlasting fire" does not mean a fire that never dies or one in which a person is eternally tormented but a fire of which the consequences are eternal. One who dies in the everlasting fire of God's punishment of sinners will be eternally dead! This is what is called the "Lake of Fire" in Revelation 20:15: "And anyone not found written in the Book of Life was cast into the lake of fire" (see also Matthew 13:40-43, 49-50). Similarly, nothingness, the state of death, is aptly described as "outer darkness."
Of this fate Paul writes in Hebrews 10:26-27, 31: "For if we sin willfully after we have received the knowledge of the truth, there no longer remains a sacrifice for sins, but a certain fearful expectation of judgment, and fiery indignation which will devour the adversaries. . . . It is a fearful thing to fall into the hands of the living God." As Jesus Himself says, "Fear Him who is able to destroy both soul and body in hell" (Matthew 10:28).
The human soul can die. We know it will die once physically (Hebrews 9:27), returning to God for safekeeping until the resurrection from the dead and the judgment (see Revelation 20:12-13). God, however, in His justice and mercy, will permanently destroy the souls of those who reject Him. "This is the second death" (Revelation 20:14), the final, eternal death for the—hopefully—few who choose it over eternal life in God's Kingdom.