The "Lambs book of Life" occurs in scripture about 9 times. It is the list of who will be saved.

19 “Behold, I give you the authority to trample on serpents and scorpions, and over all the power of the enemy, and nothing shall by any means hurt you.

20 “Nevertheless do not rejoice in this, that the spirits are subject to you, but rather rejoice because your names are written in heaven.”

21 In that hour Jesus rejoiced in the Spirit and said, “I thank You, Father, Lord of heaven and earth, that You have hidden these things from the wise and prudent and revealed them to babes. Even so, Father, for so it seemed good in Your sight.

22 “All things have been delivered to Me by My Father, and no one knows who the Son is except the Father, and who the Father is except the Son, and the one to whom the Son wills to reveal Him.”

Luke 10:19-22

3 And I urge you also, true companion, help these women who labored with me in the gospel, with Clement also, and the rest of my fellow workers, whose names are in the Book of Life.

Philippians 4:3

5 “He who overcomes shall be clothed in white garments, and I will not blot out his name from the Book of Life; but I will confess his name before My Father and before His angels.

Revelation 3:5

6 Then he opened his mouth in blasphemy against God, to blaspheme His name, His tabernacle, and those who dwell in heaven. 7 It was granted to him to make war with the saints and to overcome them. And authority was given him over every tribe, tongue, and nation. 8 All who dwell on the earth will worship him, whose names have not been written in the Book of Life of the Lamb slain from the foundation of the world.

Revelation 13:8

8 “The beast that you saw was, and is not, and will ascend out of the bottomless pit and go to perdition. And those who dwell on the earth will marvel, whose names are not written in the Book of Life from the foundation of the world, when they see the beast that was, and is not, and yet is.

Revelation 17:8

11 Then I saw a great white throne and Him who sat on it, from whose face the earth and the heaven fled away. And there was found no place for them. 12 And I saw the dead, small and great, standing before God, and books were opened. And another book was opened, which is the Book of Life. And the dead were judged according to their works, by the things which were written in the books. 13 The sea gave up the dead who were in it, and Death and Hades delivered up the dead who were in them. And they were judged, each one according to his works. 14 Then Death and Hades were cast into the lake of fire. This is the second death.

15 And anyone not found written in the Book of Life was cast into the lake of fire.

Revelation 20:11-15

27 But there shall by no means enter it anything that defiles, or causes an abomination or a lie, but only those who are written in the Lamb’s Book of Life.

Revelation 21:27

19 and if anyone takes away from the words of the book of this prophecy, God shall take away his part from the Book of Life, from the holy city, and from the things which are written in this book.

Revelation 22:19