8620. 'Write this [for] a memorial in the book' means for everlasting remembrance. This is clear from the meaning of 'a memorial' as that which should serve to remind or bring to remembrance, dealt with in 8066, 8067; and from the meaning of 'writing in the book' as to serve as an everlasting reminder. This is the meaning of 'writing in a book in Isaiah,
Come, write on a tablet among them, and express it in a book,a so that it may be for time to come, forever even to eternity.b Isa 30:8.
Since remembrance is meant by 'writing in a book', true believers are therefore said to have been 'written in the book of life'; for salvation is meant by God's remembering, and damnation by His not remembering or His forgetting. 'The book of life' is referred to in Daniel as follows,
The Ancient of Days [was seated], the judgement sat down, and the books were opened. Dan 7:9, 10.
In the same prophet,
At that time Your people will be rescued, every one who is found written in the book. Dan. 12:1.
In David,
Addc iniquity onto their iniquity, and do not let them reach Your righteousness. Let them be blotted out of the book of the living,d and not be written with the righteous. Ps 69:27, 28.
In John,
He who conquers will be clad in white garments; I will not blot his name out of the book of life. Rev 3:5.
In the same book,
None will enter the new Jerusalem except those who have been written in the Lamb's book of life. Rev 21:26, 27.
In the same book,
I saw that the books were opened. And another book was opened, which is the book of life, and the dead were judged by the things written in the books, according to their works. They were judged, all of them according to their works. And if anyone was not found written in the book of life, he was cast into the lake of fire. Rev 20:12-15.
See in addition Rev 13:8; 17:8.
[2] Anyone who does not know from the internal sense what 'the book of life' is, and also what is meant by 'the books' whose contents are to be used to judge the dead, can have no other idea than this - that such books exist in heaven, and that they contain written down in them everyone's deeds, the memory of which is thus preserved. However, by the books mentioned in the places quoted above one should not understand books but the remembrance of all the deeds they had performed. For each person takes with him into the next life the memory of all his deeds, that is, the book of his life, 2474. But judging someone according to his deeds can be done by no one except the Lord alone. For all deeds emanate from final causes,e which lie inwardly and deeply hidden; and it is according to those causes that a person is judged. These are known to no one except the Lord, which is why judgement belongs to Him alone. This is also what the following words in John are used to mean,
I saw on the right handf of Him sitting on the throne a book written within and on the back, sealed with seven seals. After that I saw a strong angel crying out with a loud voice, Who is worthy to open the book and to loose its seals? One of the elders said to me, Behold, the Lion which is from the tribe of Judah, the root of David, has prevailed to open the book and to loose its seals. And He took the book, and they sang a new song, You are worthy to take the book, and to open its seals. Rev 5:1-9
From all this it becomes clear that 'a book written' is used to mean the presence of someone's deeds. The book referred to in David has a similar meaning,
In Your book they all were written, the days that were assigned. Ps 139:16.