I think He did this way more so, prior to the Flood. Literally only eight people were saved. But by the time of the Flood, the Lamb had been slain from the foundation of the World (some say He was slain "eternally" outside of time, but at the very least it must have been right around the Fall, and not after the Flood) so the die had been cast.
"The Lamb slain from the foundation of the World" is simply conveying the idea that God had made the decision to sacrifice Himself to save some of Adam's race, should the need arise, from the very beginning.
"The Lamb slain from the foundation of the world" is a cliche that has arisen from a misreading of two passages in revelation.
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.
Bible Gateway passage: Revelation 13:8 - New King James Version
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.
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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.
Bible Gateway passage: Revelation 17:8 - New King James Version
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.
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The "Book of Life" is the title of a book in God's posession. (See below for the other places it shows up in scripture.)
"Of the Lamb Slain" is the subtitle, the Lamb slain of course being Christ crucified.
Names are written in it, and have been written in it, "from the foundation of the world."
Those whose names are NOT written in this book will worship the beast, and will marvel.
You could, in fact, write that part of 13:8 in this way, and not change the meaning:
"whose names have not been written from the foundation of the world in the Book of Life of the Lamb slain"
You could, in fact, write that part of 17:8 in this way, and not change the meaning:
"whose names are not written from the foundation of the world in the Book of Life"
Christ, the Lamb, was not slain from the foundation of the world (as Revelation 17:8 should have made clear). He died once for all!
Now if we died with Christ, we believe that we shall also live with Him, knowing that Christ, having been raised from the dead, dies no more. Death no longer has dominion over Him. For the death that He died, He died to sin once for all; but the life that He lives, He lives to God. Likewise you also, reckon yourselves to be dead indeed to sin, but alive to God in Christ Jesus our Lord.
Bible Gateway passage: Romans 6:8, Romans 6:9, Romans 6:10, Romans 6:11 - New King James Version
Now if we died with Christ, we believe that we shall also live with Him,
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For such a High Priest was fitting for us, who is holy, harmless, undefiled, separate from sinners, and has become higher than the heavens; who does not need daily, as those high priests, to offer up sacrifices, first for His own sins and then for the people’s, for this He did once for all when He offered up Himself. For the law appoints as high priests men who have weakness, but the word of the oath, which came after the law, appoints the Son who has been perfected forever.
Bible Gateway passage: Hebrews 7:26, Hebrews 7:27, Hebrews 7:28 - New King James Version
For such a High Priest was fitting for us, who is holy, harmless, undefiled, separate from sinners, and has become higher than the heavens;
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But Christ came as High Priest of the good things to come, with the greater and more perfect tabernacle not made with hands, that is, not of this creation. Not with the blood of goats and calves, but with His own blood He entered the Most Holy Place once for all, having obtained eternal redemption. For if the blood of bulls and goats and the ashes of a heifer, sprinkling the unclean, sanctifies for the purifying of the flesh, how much more shall the blood of Christ, who through the eternal Spirit offered Himself without spot to God, cleanse your conscience from dead works to serve the living God? And for this reason He is the Mediator of the new covenant, by means of death, for the redemption of the transgressions under the first covenant, that those who are called may receive the promise of the eternal inheritance.
Bible Gateway passage: Hebrews 9:11, Hebrews 9:12, Hebrews 9:13, Hebrews 9:14, Hebrews 9:15 - New King James Version
The Heavenly Sanctuary - But Christ came as High Priest of the good things to come, with the greater and more perfect tabernacle not made with hands, that is, not of this creation.
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Previously saying, “Sacrifice and offering, burnt offerings, and offerings for sin You did not desire, nor had pleasure in them” (which are offered according to the law), then He said, “Behold, I have come to do Your will, O God.” He takes away the first that He may establish the second. By that will we have been sanctified through the offering of the body of Jesus Christ once for all. And every priest stands ministering daily and offering repeatedly the same sacrifices, which can never take away sins. But this Man, after He had offered one sacrifice for sins forever, sat down at the right hand of God, from that time waiting till His enemies are made His footstool. For by one offering He has perfected forever those who are being sanctified.
Bible Gateway passage: Hebrews 10:8, Hebrews 10:9, Hebrews 10:10, Hebrews 10:11, Hebrews 10:12, Hebrews 10:13, Hebrews 10:14 - New King James Version
Previously saying, “Sacrifice and offering, burnt offerings, and offerings for sin You did not desire, nor had pleasure in them” (which are offered according to the law),
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Beloved, while I was very diligent to write to you concerning our common salvation, I found it necessary to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints.
Bible Gateway passage: Jude 3 - New King James Version
Contend for the Faith - Beloved, while I was very diligent to write to you concerning our common salvation, I found it necessary to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints.
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The book appears in a few other places in the New Testament without its subtitle:
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. I implore Euodia and I implore Syntyche to be of the same mind in the Lord.
Bible Gateway passage: Philippians 4:3, Philippians 4:2 - New King James Version
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.
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“And to the angel of the church in Sardis write,‘These things says He who has the seven Spirits of God and the seven stars: “I know your works, that you have a name that you are alive, but you are dead. Be watchful, and strengthen the things which remain, that are ready to die, for I have not found your works perfect before God. Remember therefore how you have received and heard; hold fast and repent. Therefore if you will not watch, I will come upon you as a thief, and you will not know what hour I will come upon you. You have a few names even in Sardis who have not defiled their garments; and they shall walk with Me in white, for they are worthy. 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. “He who has an ear, let him hear what the Spirit says to the churches.” ’
Bible Gateway passage: Revelation 3:1, Revelation 3:2, Revelation 3:3, Revelation 3:4, Revelation 3:5, Revelation 3:6 - New King James Version
The Dead Church - “And to the angel of the church in Sardis write, ‘These things says He who has the seven Spirits of God and the seven stars: “I know your works, that you have a name that you are alive, but you are dead.
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Then of course, the two passages I quoted above, followed by...
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. 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. 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. Then Death and Hades were cast into the lake of fire. This is the second death. And anyone not found written in the Book of Life was cast into the lake of fire.
Bible Gateway passage: Revelation 20:11, Revelation 20:12, Revelation 20:13, Revelation 20:14, Revelation 20:15 - New King James Version
The Great White Throne Judgment - 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.
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But I saw no temple in it, for the Lord God Almighty and the Lamb are its temple. The city had no need of the sun or of the moon to shine in it, for the glory of God illuminated it. The Lamb is its light. And the nations of those who are saved shall walk in its light, and the kings of the earth bring their glory and honor into it. Its gates shall not be shut at all by day (there shall be no night there). And they shall bring the glory and the honor of the nations into it. 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.
Bible Gateway passage: Revelation 21:22, Revelation 21:23, Revelation 21:24, Revelation 21:25, Revelation 21:26, Revelation 21:27 - New King James Version
The Glory of the New Jerusalem - But I saw no temple in it, for the Lord God Almighty and the Lamb are its temple.
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For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book; 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.
Bible Gateway passage: Revelation 22:18, Revelation 22:19 - New King James Version
A Warning - For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book;
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Note the passage in Revelation 21, where it refers to the book as "the Lamb's Book of Life."
No, the Lamb was not slain, literally or figuratively, from the foundation of the world. He was slain around AD 30, hanged on a tree, was buried, and rose again on the third day.