Question 1, Is the book of life mentioned in the Old Testament, the same book as the Lamb’s book of life mentioned in the New Testament. One view seems to be that it is, and my view is they are two very different books. Question 2, Is the OT book of life the only book or written record in view in the Old Testament passages, or is a second book that has the names of the righteous also being revealed? I think that a second book is being revealed. Lets start with Psalm 69:28. Here are three versions of the text:(NKJV) 28 “Let them be blotted out of the book of the living, And not be written with the righteous.” (ESV) 28 “Let them be blotted out of the book of the living; let them not be enrolled among the righteous.” (NIV) 28 “May they be blotted out of the book of life and not be listed with the righteous.” Now there are two possible readings of this verse. One, when a name is blotted out, it is removed from the list of the righteous, because the Book of Life only lists the righteous, or (two) two actions are in view, (1) the name is removed from the book of life and (2) the name is not entered in another book listing the righteous. From this text, either view is possible. Now lets turn to Exodus 32:32. Here are the three versions: (NKJV) 32 “Yet now, if You will forgive their sin—but if not, I pray, blot me out of Your book which You have written.” (ESV) 32 “But now, if you will forgive their sin--but if not, please blot me out of your book that you have written." (NIV) 32 “But now, please forgive their sin—but if not, then blot me out of the book you have written." In this passage, Moses is pleading with God to spare the people who have worshiped another god, and says in effect, if you do not forgive them, then take my life. But God answers in verse 33 that He will blot out the sinners, not Moses. This passage supports the idea that the book in view, the OT book of life, is a record of the physically living, and to be blotted out is for God to take your life. Lets turn to Psalm 139:16. Here are the three versions: (NKJV) 16 “Your eyes saw my substance, being yet unformed. And in Your book they all were written, The days fashioned for me, When as yet there were none of them. (ESV) 16 “Your eyes saw my unformed substance; in your book were written, every one of them, the days that were formed for me, when as yet there were none of them.” (NIV) 16 “your eyes saw my unformed body. All the days ordained for me were written in your book before one of them came to be.” This passage clearly teaches that when we are physically conceived, and God looks upon our unformed substance, our name is recorded along with our days of physical life, and this information is recorded before we have lived even one day. But this represents God plan for the person’s life duration, and does not preclude God altering His plan and blotting names out or extending a person’s lifetime for His purpose. This then is a good verse to support that the Old Testament book of life lists the names of those who are alive along with information concerning the duration of the person’s physical lifetime. Turning now to Daniel 12:1, here are the three versions: (NKJV) 1 “At that time Michael shall stand up, The great prince who stands watch over the sons of your people; And there shall be a time of trouble, Such as never was since there was a nation, Even to that time. And at that time your people shall be delivered, Every one who is found written in the book.” (ESV) 1"At that time shall arise Michael, the great prince who has charge of your people. And there shall be a time of trouble, such as never has been since there was a nation till that time. But at that time your people shall be delivered, everyone whose name shall be found written in the book.” (NIV) 1 "At that time Michael, the great prince who protects your people, will arise. There will be a time of distress such as has not happened from the beginning of nations until then. But at that time your people—everyone whose name is found written in the book—will be delivered.” Daniel has the end times in view, and so this seems to be referring not to the book of life having the names of everyone alive, but rather to a book listing the righteous, perhaps foreshadowing the revelation of the New Testament Lamb’s book of Life! So I conclude that two books are in view in Psalm 69:28, a record of the physically alive, and a record of the righteous – a listing of the Old Testament saints – and under the Old Covenant names can be removed from both books, God can take your life and blot you out of the Book of life, which I will call the OT book of the living, and names can be blotted out of the OT book of the righteous if a person does not maintain a faithful relationship with God. Old Covenant theology is a loss of salvation theology. But the New Covenant is superior, and once a person is saved according to the New Covenant, they are sealed with the Holy Spirit as a pledge to an inheritance of eternal life, and so God has promised to not blot names out once entered in the New Covenant Lamb’s book of life. Thus Philippians 4:3 refers to the New Covenant Lamb’s book of Life, where once you are enrolled, Jesus has promised to never remove your name. This is certified by Revelation 3:5 which states that he who overcomes, a reference to being born again by the will of God, shall not have is name blotted out.