For He [Christ] was foreknown before the foundation of the world, but has appeared in these last times for the sake of you who through Him are believers in God, who raised Him from the dead and gave Him glory, so that your faith and hope are in God.What do we get from this? Well, we know that Christ was foreknown before creation. Therefore, He is an eternal being. We know that God raised Him from the dead and glorified Him. We know that His resurrection is the basis of your faith and hope being in God. But did you catch that little statement from Peter? He said that Christ appeared in these last times "for the sake of you who through Him are believers in God."
(1 Peter 1:20-21)
Now, our tendency, given our "me" society and our "me" natures, is to think something like, "Oh, really nice! He came for me." That is, our focus is there. If it is, we miss what he said. He said that we are believers in God through Christ. That is, we don't come to faith on our own. We don't come to believe in God and then He introduces us to His Son and we become Christians -- followers of Christ. We don't figure out that God is the best option and Christ is His Son. We become believers through Christ.
It's not like it's the only reference on this. After healing the man in Solomon's Portico, Peter told the crowd, "On the basis of faith in His name, it is the name of Jesus which has strengthened this man whom you see and know; and the faith which comes through Him has given him this perfect health in the presence of you all." (Acts 3:16) Same thing. "The faith which comes through Him ..." And isn't that what we find in Hebrews when we read that Jesus is "the author and finisher of our faith" (Heb 12:2)?
Peter, writing to those "who are chosen according to the foreknowledge of God the Father" (1 Peter 1:1-2), indicates that faith in God comes through Christ. This excludes those who have faith in God apart from Christ. The language speaks literally of believing into God. Not mental acquiescence. Not just admission of fact. It is a placing absolute trust into God that is required and this only happens through Christ. And Peter says that this fact demands a response (1 Peter 1:22).