Revelation 13:8: And all that dwell upon the earth shall worship him, whose names are not written in the book of life of the Lamb slain from the foundation of the world.

Revelation 13:8 describes the Great Apostasy¹ when all that dwell upon the earth² worshiped Satan,³ either by compulsory means or through their own volition.⁴ The worship of God in spirit and in truth⁵ did not exist⁶ anywhere on the earth by anyone.⁷ Joseph Smith learned this during the First Vision in 1820, when he was told not to join any church because they were all corrupt.⁸ True worship⁹ did not and could not exist without pure doctrine,¹⁰ without apostles and prophets,¹¹ without the priesthood,¹² and without the legal administration of gospel ordinances.¹³

By the time The Church of Jesus Christ of Latter-day Saints was restored on earth in 1830,¹⁴ the doctrines and practices of the true church of Jesus Christ had been absent from the earth for almost thirteen centuries,¹⁵ and much longer in some parts of the world.¹⁶ Saints in the seven churches of Asia, for example, began to worship Satan¹⁷ by following and serving him¹⁸ in differing degrees¹⁹ by the time John wrote his seven letters to them in 96 AD.²⁰

Worshipers of Satan are those that do not have their names written in the book of life of the Lamb.²¹ This book of life contains the names of people that qualify for exaltation in the celestial kingdom.²² Some people are foreordained to eternal life before their mortal birth and have their names written in the book of life before they are born.²³ However, they must still qualify for this blessing given to them conditionally. If they fail to qualify by obedience to the gospel of Jesus Christ, then their names will be blotted out.²⁴ Righteous people can also have their names added to the book of life in mortality²⁵ by obedience to gospel law.²⁶ This was not possible during the Great Apostasy, however, because the true church was not on the earth²⁷ and all that dwelt upon the earth worshiped Satan.²⁸

God appointed people to live on earth during the Great Apostasy²⁹ when the gospel was not available to them.³⁰ Many were appointed to be born at this time because they did not have their names in the book of life and were not foreordained to receive eternal life during their premortal existence.³¹ There are some obvious exceptions, however. For example, little children that died before the age of accountability during the Great Apostasy will receive eternal life.³² Also, those that would have received the gospel with all their heart if it had been available to them³³ can receive the gospel in the postmortal spirit world³⁴ and then receive eternal life.³⁵ This latter group includes many righteous saints who were devoted followers of Jesus Christ during the Renaissance and Reformation. Their faith-filled sacrifices paved the way for the restoration of the gospel in 1830.³⁶

The Lamb slain from the foundation of the world refers to Jesus Christ.³⁷ This title means that before the creation of this earth, Christ was chosen and foreordained to die on this earth as an atoning sacrifice.³⁸ The book of life is his book because Christ is the way, the truth, and the life.³⁹ He is the ultimate judge of those who qualify to have their names written in the book of life.⁴⁰