What happens to those not written in the book of life?

According to Revelation 21:8, those whose names are not written in the book of life will encounter severe consequences, including the second death, which is eternal separation from God. This distinction highlights the importance of God's grace and sovereignty in salvation, emphasizing that only those chosen and called by Him will inherit the new creation. The passage serves as a sobering reminder of the fate awaiting the unrepentant, contrasting the hope of eternal life with the reality of judgment. It reinforces the essential Reformed understanding of election and the necessity of God's mercy in salvation.