2 Timothy 1:8-10
So do not be ashamed to testify about our Lord, or ashamed of me his prisoner. But join with me in suffering for the gospel, by the power of God, who has saved us and called us to a holy life--not because of anything we have done but because of his own purpose and grace. This grace was given us in Christ Jesus before the beginning of time, but it has now been revealed through the appearing of our Savior, Christ Jesus, who has destroyed death and has brought life and immortality to light through the gospel.
Tell me, if God didn't know that Adam would fall, why did God already plan to give us grace through Jesus Christ, before He even started creating the universe? Explain that passage...
Felgar, let me give you a bit long answer to your short question. I have given this to somebody who asked me the same question you asked. You might find this very pedantic or even naí¯ve but please bear with me.
God perfectly knew that Adam might possibly fall or might possibly not fall. He perfectly knew these possibilities and He also perfectly knew the entire ramifications of these possibilities and He also perfectly knew what He needs to do to all these possibilities in mind. As it is, one of the possibilities was that Adam would fall and one of the ramifications of this fall was man's rebellion and then hell. Because of these possibilities (fall or no fall) God predestined Christ's death in case of a fall. IOW, the Christ's death is contingent on the fall of Adam (which is one of the possibilities). All these possibilities and all the possible ramifications and all moves God would make are in the eternal mind of God who is infinitely intelligent to mentally conceive all these things as if He's mentally conceiving only one certain event!
Now, let's go back to Adam. God perfectly knew that Adam might possibly fall (possibility A)
or might possibly not fall (possibility B)
and He perfectly knew the possible ramifications of these two possibilities (let's name them A-1, A-2, B-1, B-2, etc.). Not only that, God also perfectly knew what actions to be done to A & B and also to A-1, A-2, B-1, & B-2 (let's call these actions A-X, B-X, A-1-X, A-2-X, B-1-X, etc.). Thus, in the infinite mind of God there exist AB and at the same time there exist A-1, A-2, B-1, & B-2 and at the same time there exist A-X, B-X, A-1-X, A-2-X, B-1-X, etc. IOW, God's infinite mind was filled with infinite possibilities. Now let's look at this way (pardon my finite and fallible way of conceiving what originally took place):
Now, here's God at one point in eternity saying, "I want to create a free moral agent who will love me by his own volition and own free will and not Myself causing him to love Me. I will call him 'man.'" But God knew the possibilities, so He said, "But if I will make him a free moral agent, the possibilities are: he might sin (A) or he might not sin (B)." So God decided: "Okay, for A, I decide that I will do this - death of Christ (i.e., the giving of grace). And for B, I decide that I will do this - perfect environment or eternal bliss. But of course my heart's desire is that man would not fall so that I could give Him the eternal bliss. Of course, I don't want him to fall, but if he would choose that, I decided that My Son would die for him."
This plan (if I may call it a plan) was done or determined in eternity pass.
After billion of years the time came for man to be created by God. God was very pleased with His creation, so He called it "very good" (although God perfectly knew it's possible for his creation to fall, his creation can still be called "very good" because God perfectly knew also that His creation might possibly NOT fall. Unlike in the other view that says God knew that His creation would certainly fall, calling His creation "very good" is quite amiss.)
God chose to believe man that he wouldn't fall although in His mind possibilities AB, A-1, A-2, B-1, etc. still lingers or better yet, still exist. Because of this action (i.e., choosing to believe that man wouldn't fall), God enjoyed genuine fellowship with man in the Garden of Eden. On the other hand, if God certainly knew that man would definitely sin and because of that He "left him out" from eternity past, then no genuine fellowship would have taken place between man and God in the Garden.
Then came the Fall. The story after the fall fits in very well to the concept I presented, at least, IMHO. God's lament over Eve's disobedience: "What is this you have done?" (Gen. 3:13) fits in very well. As if God was saying, "Why did you choose to disobey Me?" Such questioning cannot fit in if God certainly knew Adam would fall. In Genesis 6 we read in verse 6: "The Lord was grieved that he had made man on the earth, and his heart was filled with pain." God was disappointed and He was grieving and hurting. Why? Because he took the risk of choosing to believe that man wouldn't fall, and yet he did. I could say, therefore, that when God grieved here, His grieving was genuine and real and not merely a charade, which is one of the implications if one says that God certainly knew, throughout the gamut of eternity, that man would sin. For how can God be genuinely saddened by man's sin in time when all along eternity He has in His mind and heart that man would certainly sin, let alone that according also to traditoinal proponents past, present, future are one "eternal now" to God, meaning to say, that the actual commitment of sin was no different at all from what God have in mind and heart from eternity to eternity, so how could He possibly genuinely grieved given that kind of scenario. In fact, even the "moment" of His grieving was already "there." It's not a new "experience" in God's personality anymore.
Now what about the argument that "if God didn't know that Adam would fall, why did God already plan to give us grace through Jesus Christ, before He even started creating the universe? We should note that there is no scripture that says that God certainly knew Adam would fall. The idea is only a deduction from a particular verse of scripture (and the likes). But how sure are we that it's the case? One of those verses is 2 Timothy 1:8-10: It reads:
“So do not be ashamed to testify about our Lord, or ashamed of me his prisoner. But join with me in suffering for the gospel, by the power of God, who has saved us and called us to a holy life--not because of anything we have done but because of his own purpose and grace. This grace was given us in Christ Jesus before the beginning of time, but it has now been revealed through the appearing of our Savior, Christ Jesus, who has destroyed death and has brought life and immortality to light through the gospel.”
The argument goes: if God didn't know that Adam would fall, why did God already plan to give us grace through Jesus Christ, before He even started creating the universe? Do these verses pose a problem to the view I presented? Not really. God decided or planned that the grace be given us IN CHRIST before creation because God knew that possibility A
(i.e., Adam falling) could take place and therefore it can be said by Paul during his time
that “This grace was given us in Christ Jesus before the beginning of time.” There's no indication in those verses that God knew FOR CERTAIN
from eternity that Adam would fall.