What does the Bible say about God's eternal book?

The concept of God's eternal book is found in Revelation 21:27, which notes that only those whose names are written in the Lamb's book of life will enter the heavenly city. This signifies that salvation is not random or arbitrary but predetermined by God's grace. The book emphasizes the security of the redeemed, as their names inscribed there confirm God's purpose for their salvation. As Mike McInnis notes, considering that grace first inscribed our names in God's eternal book inspires profound comfort, since it indicates that our salvation rests not on our merit but solely on God's grace.