What is the second death the Bible talks about?

TL;DR:

The second death is eternal separation from God in the lake of fire, reserved for those who reject Christ. Believers in Jesus will never face the second death because His victory secures eternal life.

what does the bible say?

The Bible speaks of the “second death” as the final judgment where those outside of Christ are cast into the lake of fire (Revelation 20:14). The term distinguishes between physical death—the first death that all people face because of sin—and the ultimate, eternal death that follows for those who do not belong to the Lord (Romans 6:23). This death is not annihilation but ongoing separation from God, marked by conscious punishment (Matthew 25:46).

While the Old Testament does not use the phrase “second death,” it prepares the way by warning of judgment beyond physical death (Daniel 12:2). The New Testament then clarifies that those who overcome through faith in Christ will not be hurt by the second death (Revelation 2:11). Instead, the second death is reserved for Satan, his demons, and all whose names are not found in the book of life (Revelation 20:15). Because Jesus bore sin’s penalty, believers die once physically but live eternally with Him, safe from the second death (John 11:25–26; Hebrews 9:27–28).

from the old testament

Physical death (the “first death”) is the penalty for sin. This is what God meant when He punished Adam, saying, “you are dust, and to dust you shall return” (Genesis 3:19). However, the prophets were given insight that more awaited humanity than the grave alone.
For example, Daniel described a resurrection in which “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). This distinction between everlasting life and everlasting judgment anticipates the New Testament’s teaching on eternal destiny with “everlasting contempt,” what the New Testament calls the “second death.”
Isaiah also looked ahead to the “second death” fated for the wicked, declaring that “their worm shall not die, their fire shall not be quenched” (Isaiah 66:24). This image portrays unending judgment for those who rebel against God.

from the new testament

The New Testament introduces the phrase “second death” and explains it as the eternal destiny of the unrepentant. Revelation 20:14–15 defines what it is: “Then Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire. And if anyone’s name was not found written in the book of life, he was thrown into the lake of fire.” The second death is not dying again, but the state of eternal punishment for those who are judged guilty before God.
Jesus warned of this reality. Using language borrowed from Isaiah 66:24, He spoke of hell as the place “where their worm does not die and the fire is not quenched” (Mark 9:48). He described it as “outer darkness” a place where “there will be weeping and gnashing of teeth” (Matthew 8:12; 25:30). These images stress not only the finality of the “second death,” but also the conscious torment and separation from God’s presence found there.
Hebrews reminds us that “it is appointed for man to die once, and after that comes judgment” (Hebrews 9:27). Physical death comes first (and to everyone except those alive at Jesus’ Second Coming), but judgment after death leads either to eternal life or to the second death. So, the second death stands in contrast to eternal life. Paul explained, “the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord” (Romans 6:23).
At the final judgment, books are to be opened and “the dead were judged by what was written in the books, according to what they had done.” (Revelation 20:12c). One of the books will be the Book of Life, which has the names of all who have trusted in Jesus. Therefore, “if anyone’s name was not found written in the book of life, he was thrown into the lake of fire”---the second death (Revelation 20:15). Those who belong to Christ will not be touched by the second death but will inherit eternal life (Revelation 2:11).

implications for today

The Bible’s teaching on the second death is both a sober warning and a source of deep assurance. For those who have not trusted in Jesus, it highlights the seriousness of sin. Physical death is not the final punishment for those who rejected God. Because He is eternal and because every sin is against Him (Psalm 51:4), then judgment must also be eternal. The lake of fire is more than simply not being with God; it’s also God actively pouring out punishment against each man and woman in it.

For the believer, however, knowledge of the second death is a source of hope. Jesus declared that the one who believes in Him “will never die” (John 11:26). While Christians still face physical death, they will never experience the second death. Additionally, the believer also knows that the second death represents God’s perfect justice. No injustice in this life will ultimately be unpunished. So, while the believer does not want anyone to go there, he or she is also comforted knowing that God’s justice will be satisfied.

Because of this, knowledge about the second death should compel believers to share the gospel because it is the eternal destiny for friends, neighbors, and family members who do not know Christ. Pray for them and tell them the truth, pointing to the only Savior who delivers from that destiny.

For everyone, the eternal second death calls you to examine your own heart: is your name truly written in the Lamb’s book of life? If so, rejoice! But, if not, turn to Christ today for forgiveness and eternal life.

understand

The second death is eternal separation from God for those who reject Christ.
The second death follows physical death and involves conscious punishment.
Believers in Jesus are saved from the second death and have eternal life.

reflect

How does the reality of the second death affect the way you live out your faith?
How can you be confident that your name is written in the Lamb’s book of life, and what does that assurance mean for you?
How might your understanding of God’s justice and mercy shape your conversations about salvation with others?

engage

How do we explain the difference between physical death and the second death clearly and compassionately?
How can the reality of the second death motivate us to share the gospel with friends, family, and others in our community who have not yet trusted in Jesus?
How does the promise of being saved from the second death strengthen our hope and faith in Christ?