"A man can accept what Christ has done without knowing how it works: indeed, he certainly would not know how it works until he has accepted it" (C.S. Lewis in Mere Christianity). As a Lutheran, I do not believe a person can accept anything about Christ, but rather receive it from Him through the faith which the Holy Spirit gives him. However, this belief does not change the meaning of Lewis' statement: a person can receive Christ as his Lord and Savior without knowing exactly how His salvation works exactly. Now, this does not mean that He does not know Christ died for Him, for that is vitally important to the Christian faith. In fact, without that faith, there is no Christian faith. What it does mean is that God's love and salvation transcends all human understanding, and that it is only by faith that we are saved; but also that once we are given this faith, our salvation makes all the sense in the world.
This may require some explanation. In order to be saved, one must believe that Jesus Christ, both God and man, came to earth, died, and rose again from the dead. Faith in this belief will save anyone who shares in it. Now here is what is completely illogical to most people: there is nothing a person can do by themselves to get to heaven; it is all done by God. Romans 7:18-20 says, "For I know that nothing good dwells in me, that is, in my flesh. For I have the desires to do what is right, but not the ability to carry it out. For I do not do the good I want, but the evil I do not want is what I keep doing. Now if i do what I do not want, it is no longer I who do it, but sin that dwells within me." Here Paul is saying that humans, no matter how good they seem to us, are incapable of being truly "good." Here is the amazing part though: "There is therefore no condemnation for those who are in Christ Jesus" (Romans 8:1).
The point here is that we do not have to do anything to achieve salvation; it is already done for us by Jesus. This kind of love, sacrifice, devotion, patience, and mercy are absolutely incomprehensible to the human mind, and because of that it is sometimes hard to believe. This is where faith and prayer become so important: Hebrews 11:1 says, "Now faith is the assurance of things hoped for, the conviction of things not seen." Unless we do not have faith in this sacrifice by Jesus, it will not make sense to us. Christianity, from the outside, seems completely ridiculous. It is hard for people to understand why we believe what we believe and do what we do for the glory of our Heavenly Father. That is why it is so important for us to live our faith and share it with everyone. The state of being outside Christianity and viewing it as ridiculous is what Jesus was referring to when he talked of spiritual darkness. In fact, until Jesus came, the entire world was engulfed in this darkness: John 1:5- "The light shines in the darkness, but the darkness has not overcome it." Jesus is the light, and He shines through us who receive Him as our Savior and reflect his light to the world.
Once a person has come into the light, faith makes sense of all things. This does not mean that everything is comprehensible; but rather that the person has the complete assurance that God has a purpose, plan, and will always be there for every individual who calls on His name. Paul writes in 2 Corinthians 4:18, "as we look not to the things that are seen but to the things that are unseen. For the things that are seen are transient, but the things that are unseen are eternal" That is the peace Christians have: no matter what happens, no matter how confusing things might be to our pathetic, human minds, we can be assured that there is a sense behind everything that goes far beyond anything we can imagine; and that our God, who loves us, is watching over and taking care of us... and always will be.