This chain of events was set in motion a long time ago.

The following from Spurgeon is an inspiring thought regarding justification, confidence/assurance of the believer, and subsequently the extent of the atonement. It deals with substitutionary atonement, the impossibility of double jeopardy due to God being just, and the grounds of a believer's confidenc/assurance being in the certainty of payment.

"Just, and the justifier of him which believeth." Romans 3:26

Being justified by faith, we have peace with God. Conscience accuses no longer. Judgment now decides for the sinner instead of against him. Memory looks back upon past sins, with deep sorrow for the sin, but yet with no dread of any penalty to come; for Christ has paid the debt of his people to the last jot and tittle, and received the divine receipt; and unless God can be so unjust as to demand double payment for one debt, no soul for whom Jesus died as a substitute can ever be cast into hell. It seems to be one of the very principles of our enlightened nature to believe that God is just; we feel that it must be so, and this gives us our terror at first; but is it not marvellous that this very same belief that God is just, becomes afterwards the pillar of our confidence and peace!

If God be just, I, a sinner, alone and without a substitute, must be punished; but Jesus stands in my stead and is punished for me; and now, if God be just, I, a sinner, standing in Christ, can never be punished. God must change his nature before one soul, for whom Jesus was a substitute, can ever by any possibility suffer the lash of the law. Therefore, Jesus having taken the place of the believer-having rendered a full equivalent to divine wrath for all that his people ought to have suffered as the result of sin, the believer can shout with glorious triumph, "Who shall lay anything to the charge of God’s elect?"

Not God, for he hath justified; not Christ, for he hath died, "yea rather hath risen again." My hope lives not because I am not a sinner, but because I am a sinner for whom Christ died; my trust is not that I am holy, but that being unholy, he is my righteousness. My faith rests not upon what I am, or shall be, or feel, or know, but in what Christ is, in what he has done, and in what he is now doing for me. On the lion of justice the fair maid of hope rides like a queen."
-Charles Haddon Spurgeon in Morning By Morning (9/25)

If payment for sin has already been made, God would be extracting double payment if someone for whom Christ died. That would be unjust. Consequently, if Christ died uniformly for everyone individual human so that their sins were atoned for, they would not have to go to hell. In other words, a universal atonement would lead to universalism, assuming God is just, which Spurgeon and I do.

If God demanded payment for one whom Christ died for, then He could exact payment from us who believe. Since God is just we have confidence that He cannot violate His character and therefore will not punish those for whom Christ has already been punished.

The Lord Jesus, however, laid down His life for the sheep (John 10:11, 15). Before the creation of the world, God's plan was that Jesus die as a Redeemer. This chain of events was set in motion a long time ago as God's eternal plan was conceived (Rev 13:8). Because God always accomplishes His plans (Job 42:2), we have confidence that God's plan will be successful, that those Christ came to save will indeed be saved.

From this I am reminded of the words of the song "In Christ Alone," which also ties into the theme of God's providence.

No guilt in life, no fear in death,
This is the power of Christ in me;
From life's first cry to final breath,
Jesus commands my destiny.
No power of hell, no scheme of man,
Can ever pluck me from His hand;
Till He returns or calls me home,
Here in the power of Christ I'll stand!
-Stuart Townend / Keith Getty

For those in Christ, there is justification. There is no fear of sin's penalty, for Jesus paid it all. All to Him I owe. Sin had left a crimson stain. He washed it white as snow.