In short, eternal death is the fate that awaits all people who ultimately reject God, reject the gospel of His Son, Jesus Christ, and remain in their sin and disobedience. Physical death is a one-time experience. Eternal death, on the other hand, is everlasting. It is a death that continues through eternity, a spiritual death that is experienced on a continual basis. Just as spiritual life, by grace through faith in Christ (Ephesians 2:8-9) is everlasting life, eternal death is never-ending.
The most important question to be answered is “Does the Bible teach the doctrine of eternal death?” If the Bible doesn’t teach eternal death, then we can pack up and go home because there is no further debate on the issue. God’s Word, the Bible, is the infallible rule of faith and practice, and as such we must believe and teach only what it clearly teaches, and the Bible clearly teaches the doctrine of eternal death. We can point to several passages that explicitly state this, but for our purposes, only three will be needed, one from the Old Testament and two from the New.
• And many of those who sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt. (Daniel 12:2 ESV)
• And [the wicked] will go away into eternal punishment, but the righteous into eternal life. (Matthew 25:46 ESV)
• And if anyone’s name was not found written in the book of life, he was thrown into the lake of fire. (Revelation 20:15 ESV). In verse 10, we are told that the Lake of Fire burns “forever and ever.”
All three of these passages (and more could have been added) have as their main context the scene of final judgment. In other words, when Christ returns, three things will occur: 1) The general resurrection of “the living and the dead”; 2) the final judgment; and 3) the inauguration of the eternal state. Each of these passages demonstrates that during the final judgment of all people, Jesus will separate the righteous from the wicked. The righteous will be ushered into the final state of glory, while the wicked will be sent to the lake of fire for eternal punishment and torment. Note too (particularly in the Daniel and Matthew passages) that the same adjective (“everlasting” or “eternal”) is used to modify both “life” and “punishment/contempt.” What is true about one (life) must be true about the other (punishment), that both are eternal and last forever.
The doctrine of eternal death is not a popular doctrine to teach or proclaim. To do so often opens one up to scorn and ridicule. However, we must not let that detract us from what the Bible so clearly teaches; namely, that due to our being born in sin and trespasses, we are under the just condemnation of God for our sin. If we do not embrace the saving message of Jesus Christ, we will perish in our sin and trespasses and be under God’s just judgment for our sin—eternal death. This is a sobering doctrine and requires the utmost care and compassion in its presentation.