God’s record of the righteous began long before the New Testament was written. It is a book open enough for the righteous to know whether their names are written in it

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

010718 Is My Name Written There PP