Let's begin with the most fundamental question of all. Christianity exists because of who Jesus Christ truly is. To begin to understand Jesus, we need to start from the very beginning...
God created all things, including and especially, human beings. And while God is morally perfect, we are not. Nobody can deny that mankind is capable of the most wicked acts imaginable; gruesome violence, deceit, marital infidelity, emotional blackmail... we could make quite a list of the terrible things that people do to one another. But to give you an idea of just how morally perfect God is in comparison to us, let's consider the very first sin that mankind ever committed. The first people that God created were Adam and his wife Eve, and they lived in a garden. God forbade them to eat the fruit from a certain tree in the garden. This was, as far as they knew, the only rule that God had required them to obey. Yet both of them ate the fruit from that tree. And when they disobeyed God in this way, God had said that they would die. Whilst that seems harsh for such a small act of disobedience, it was disobedience nonetheless, and all disobedience toward God is a sin worthy of death. This act demonstrated a variety of sins, really... there was distrust of God, and pride against God, and a desire to become independent of God. We're so accustomed to sin that we all fail to understand just how sinful we are in God's eyes. We're kind of “desensitized” to sin, so that most people will tell you that they're a pretty good person... law abiding, respectful to others, charitable... but the truth is that there is not one person who, in God's eyes, isn't utterly sinful throughout. The Bible says that even “all our righteous deeds are like a polluted garment.” (Isaiah 64:6). Even the good things we do are polluted by selfish motives, envy, insincerity, a desire to be righteous apart from God; the list goes on.
Now, because God is perfectly just, sin must be judged accordingly by God. And the just consequence for sin, when you look at it from the moral standard of God, is death. Now when the Bible speaks of death, it will often be referring to the eternal death of the soul, which is ultimately an eternity in hell. But if you're thinking “even for all my most wicked deeds, surely an eternity in hell is far more than I deserve”, then you still haven't understood the gravity of sin in the eyes of God, who is perfect.
But God loves us all far more than you can imagine. Seeing the destiny of mankind, God provided a means of salvation in His Son, Jesus Christ. Jesus Christ can save you from an eternity in hell because of who He is. Perhaps the impression many people have of Jesus is that He was a great spiritual leader and philosopher who challenged the way people thought. And because He was such a radical for his time, certain people reacted against Him and put Him to death. But the Bible records three occasions during Jesus' teaching career when God Himself spoke from heaven to speak directly about Jesus. He said, for example:
This is my beloved Son, with whom I am well pleased; listen to him. (Matthew 17:5)
When God called Jesus “Son”, He was saying something that was well understood to the people of the time. God was identifying Jesus as equal to God. That is, Jesus was both God and man. Here's how the people of the time understood it when Jesus, in another place, referred to Himself as the “Son of God”:
This was why the Jews were seeking all the more to kill him, because ... he was even calling God his own Father, making himself equal with God. (John 5:18)
The fact that Jesus was both God and man is absolutely essential to the identity of Christ. If it were not so, Jesus could not save us from our sins. Since all men are sinners, but God is not, Jesus Christ was able to live a perfectly sinless life while He was on this earth.
How does that relate to our salvation from hell, since we are still sinners? As I'm sure you are aware, Jesus was crucified and put to death. The Bible says that “the wages of sin is death”, which is why we all must die. But Jesus, being sinless, did not have to die. However, He paid this price voluntarily on our behalf. Jesus gave His own life and suffered even the spiritual death that we deserve. Because of that, it is just in God's eyes to substitute the death of His Son for the penalty we must pay. The reason that this is possible is because Jesus is also God Himself, and the “value” of His death is sufficient for us all. Through faith in Christ, we receive this “propitiation”, as the Bible calls it...
[We] are justified by his grace as a gift, through the redemption that is in Christ Jesus, whom God put forward as a propitiation by his blood, to be received by faith. (Romans 3:24-25)
Finally, as proof that Jesus' death was effectual, Jesus rose again from the dead. The Bible says that “If Christ has not been raised, then our preaching is in vain and your faith is in vain.” (1 Corinthians 15:14). The reason our faith would be in vain is because it would prove that Christ's self sacrifice was ineffectual. But because Christ was raised from the dead, we can believe that we, too, can be. Because of the uniqueness of Christ Himself, there can only be one way to salvation, and that is through faith in Jesus Christ.
Well, at the moment there are many questions we have left unanswered, but over the next 100 days I'll be attempting to answer many of them. Until tomorrow, I leave you with this:
And there is salvation in no one else, for there is no other name under heaven given among men by which we must be saved. (Acts 4:12)