The Lamb Slain from the Foundation of the World !
Rev 13:8
8And 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.
Since Salvation is through the Death and Blood of Christ, the Holy Spirit does signify that the Salvation or Redemption of God's Elect was virtually accomplished before the world began ! You see, in the Mind and Purpose of God, Christ was slain from Eternity as The Elect's Covenant Head and Surety. In this statement the Father is said to have given His Son for the Redemption of His Elect before the world began. Had it not been for the Eternal accomplishments of Grace in God's Eternal Purpose or Eternal Covenant as Per
Rom 8:29-30 Eph 1:3-6
2 Tim 1:9
9Who hath saved us, and called us with an holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus before the world began,
God would have destroyed this world the moment Adam Transgressed. God's Longsuffering with the reprobate is because of God's Eternal Election and Purpose of Grace towards His own Elect
2 Pet 3:9
9The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward[The Elect], not willing that any should perish,
but that all should come to repentance.
Thats Because Christ death effects Repentance for all whom He died. There will be no repentance after Christ Return. This is where the False Teaching of Universalism is exposed, teaching that all men without exception will be saved, even if it is after the Second Coming.
The reason why the world exists even to this moment with all the wickedness and sin of the Reprobate is because of the Lamb of God slain for His People before the world began, and they must experience conversion. Everything in the OT scriptures points to Christ having been slain, past tense Ps 22;40;69;85;89; Isa 53. In every generation beginning with Abel to Malachi, the sacrifices were offered in Faith, being foundational upon the Divine Revelation that the only Hope of acceptance with God is by the Blood of the Lamb Slain from the foundation.
1 Pet 1:20. God considered Christ as the Lamb Slain from Everlasting
Mic 5:2, and saw His Chosen in Him as Redeemed, Forgiven, and Justified, and Accepted in the Beloved
Rom 8:29-30;
Eph 3:1-6, and when Christ was about to die, The Father says
Jn 12:28b
Father, glorify thy name. Then came there a voice from heaven, saying,
I have both glorified it, and will glorify it again.
And so Christ actually was Slain according to the Eternal Purpose of God, which was immutable
Acts 2:23;
4:27-28;
1 Pet 1:18-20 !
And this Purpose was manifested in time at the Cross. Whats done in the Eternal Purpose of God's Mind, is done before it actually comes to past in time, the Reality of Christ Death [In God's Mind] was a Reality way before it became an actual reality in time, this is an element of God being a Eternal Being, but we creatures of time, so we cannot measure time events as God does.