This explains the core of what orthodox Christianity is all about. It assumes the Bible is true in order to see exactly what Christianity teaches, and defends the orthodox view of the Bible, and how Jesus provided salvation for us.
The foundation of the Gospel of Jesus Christ rests on the fact that humanity chose to reject God, and because of this needed to pay the price of death. God loved humanity, but also needed to have this law fulfilled and His wrath towards their sin propitiated. In order to accomplish both of these He sent His Son to be a substitute and take the penalty of mankind in order to save them from their fate, and to renew their relationship with Him. Jesus, God the Son, became flesh so that He might represent humanity as well as fulfill the law, while at the same time taking on the guilt of all of humanity as well as defeating sin by being fully God. Because of this action, God’s wrath is propitiated, God’s love towards humanity is demonstrated, and God’s grace and mercy is poured out.
When Adam sinned, He did more than just make a mistake. He single handedly placed guilt upon the entire human race. The sin itself needed payment of death. (Romans 6:23) The sin corrupted Adam, installing a sin nature into himself and all of humanity. (Romans 5:12) This sin also brought on the wrath of God that needed to be appeased, one way or the other. (Romans 2:1-16) God could not simply forgive sin, because that would not be just. (Romans 3:25-26) However, He also could not just ignore the situation and allow humanity to be destroyed, because that would not be loving. (John 3:16) Also, if God had allowed humanity to be destroyed, He would have created something in His image that failed, and by God’s creation being a failure, that would then make God look like a failure.
For humanity to be saved, the laws in place needed to be fulfilled, and the attributes of God needed to be respected. Animal sacrifices weren’t good enough because they needed to be done over and over, and even then, they could only mask the sin, not take it away. The only one that could save humanity from its sin was the one who created humanity. The weight of the sin of humanity was so great that no finite creature could bear the full weight of the guilt. Only an infinite being, God, could do such a thing. The salvation of humanity could not come from humanity, because you “cannot put straight in others what is warped in yourself.” (Athanasius Pg. 42) At the same time, salvation did need to come from humanity, in order for the responsibility to be fulfilled. Since humanity had the guilt, it was humanity that needed to pay the price. The act of salvation needed to come from man, but it also needed to come from God. Men weren’t capable of this feat, since they are only created in the image of God. It could not come from angels, because they aren’t even created in the image of God. Only God could save humanity from the penalty they owed, and the only way God could accept the responsibility is if He became a member of the human race. In this way, God the Son, Jesus Christ, became a part of humanity, in order to save humanity from its own fate that it brought upon itself. (John 1:14)
Jesus Christ proved that He was divine by His works, (John 10:38), but also proved that He was human through His physical body (Luke 4:2). Jesus had both a human nature, in order to properly represent humanity, and a divine nature, in order to have the power to pay the price for all. In order to demonstrate His membership to both humanity and divinity, Jesus was born from a virgin. This point is often overlooked, but it’s far more crucial than a mere miraculous birth. The Spirit descended upon Mary, and caused her to become pregnant. Had she become pregnant through sexual intercourse with a man, then how could Jesus have been divine? Had Jesus not come from a woman at all, then how could He have been human? By Jesus coming from a virgin, it proved that He was a part of humanity, but also from God. In this way Jesus acts as a mediator between humanity and God. He is the only one able to bridge the gap, because He has both a human nature and a divine nature.
In order for Jesus Christ to pay the price of sin for others, He needed to be sinless Himself. If He had sinned, then His death would only be a payment for His own sin, and could not possibly be a price for other’s sins. Even by simply being born in the human race He should have acquired sin and the sin nature, but since Jesus was born of a virgin, there was no man to bring the sin nature into Him, since it is through the man that the sin nature enters a child. (Romans 5:12) Since the Holy Spirit came upon Mary to cause her to conceive, the Child was born holy. (Luke 1:35) Through His life, Jesus Christ remained uncorrupted by sin in order that He might end the corruption of sin for all others. He lived a perfect life in order to fulfill the law. (Matthew 5:17)
The fact that Jesus was God, was born holy, and was without a sin nature does not mean that He did not face temptation. Jesus faced temptation while He was in the desert fasting (Luke 4:2), and this temptation was real. However, at the same time, the Bible does tell us that God cannot be tempted. (James 1:13) The reconciliation of these two facts comes with knowing that Jesus had two natures, one human, and the other divine. Some of the things Jesus did were through His human nature, for example His hunger, thirst, and tiredness. Other things He did were through His divine nature, such as His miracles, wisdom, and knowledge. One excellent example of the two natures of Christ being evident in the same moment is when He calmed the storm. (Mark 4:35-40) Here Jesus is physically tired, but at the same time controlling the weather. It is in this way that Jesus was tempted. The human nature of Jesus Christ was tempted, but the divine nature could not be tempted, and prevented Him from sinning. An easy way of thinking about this situation is that Jesus Christ limited Himself in many respects to His human nature, but at the same time He was fully divine, which acted as a back-up for Him, protecting Him from anything outside the Father’s will.
In order for God to prove His justice, He needed to pour out His wrath. In order for God to prove His love, He needed to save humanity from their state. In order for God to save humanity from the bondage of sin, He needed to live out His life, fully abiding by the law, in order to fulfill the law on behalf of all of us. Jesus Christ was a substitute for every member of humanity. He not only took our place to take the penalty for our sins, but also took our place in order that His perfect life stands in for our sinful lives. By this action, we are no longer subject to the laws of the Old Testament. If Jesus only needed to pay the penalty of death for us, then all He needed was to be sinless, and could have died as an infant for all of humanity. Instead, Jesus lived His life, fulfilling the law, to break us from that bondage.
In order for the death of Jesus Christ to have the full impact on humanity, and have His actions properly recognized and understood, He needed to be publicly murdered in the form of crucifixion by the people, had His blood shed, and then rise again on the third day. If Jesus had not been publicly murdered by the people, but instead had died peacefully and alone, the full understanding of His action would have been lost to humanity. Firstly, if Jesus had died alone, then there would be no witnesses to guarantee that He had actually died. By a large group of people gathering for His public execution, it was obvious to everyone around that Jesus did in fact die. Secondly, if Jesus had died peacefully, it would have seemed as if He had died of His own natural limitations. Instead, Jesus was killed. There was a forceful stop to His life, showing that it was not simply His nature that caused Him to die. Thirdly, had Jesus not been crucified, some would have questioned the strength of His resurrection. A good analogy for this is that a wrestler does not choose his opponent, or else people would assume he chose an opponent that he knew he could defeat. In the same way, the people inflicted a terrible death on Him, by their own choice, to prove that Jesus Christ had ultimate power over death. Fourthly, if Jesus had not had his blood shed, for example if He had just been hung, then the Old Testament laws of sacrifice would not have been fulfilled. (Leviticus 17:11) By His blood being shed, there was remission of sins where there would not have been otherwise. (Hebrews 9:22, Revelation 1:5) Fifthly, had Jesus not risen again specifically on the third day, the impact might have been missed. Had He risen again immediately afterwards, some, if not many, would have assumed He didn’t actually die. Also, if Jesus had risen much later, people could easily assume that this was another man claiming to be Jesus. Because the actions and memories of Jesus were still fresh in the crowd’s minds, they knew that Jesus had died, and knew that this risen man must be Him.
Through the resurrection of Jesus Christ, He ultimately defeated the powers of sin and death. (Romans 6:6) Because Jesus is one of the persons of God, He cannot die, so when His human nature faced death, His divine nature kicked in and defeated death. This is how Jesus Christ was able to rise from the dead by His own power. This way, the verse “the wages of sin is death” has both been fulfilled and defeated. Jesus did die, and was a substitution for all of us in this way, but at the same time He rose again, defeating the powers of death and sin in a single blow. If Jesus had not defeated death, but merely stopped death from acting, then the fear of death would still be with humanity. However, by defeating death and rising again, we have hope, and can stand strong in the face of the defeated spirit of death. This is why Christian martyrs like Stephen have such strength. Just as Jesus is our substitution who takes our sins, and the substitution for our lives to fulfill the law, so He is our substitution in death and resurrection. Just as the death of Christ defeated death, so we died with Him and are free from death. Just as Christ rose again with a glorified body, so too shall we rise again with a glorified body. (Philippians 3:21)
The whole point of Jesus becoming a part of humanity was so that He might die. (Isaiah 53:4-10) If Jesus had not come bodily, in human form, He could not possibly have died. He bore the guilt of our sins, allowed the wrath of the Father to be poured out on Him, and shed His blood, all so that He could take our penalty as a substitution for us, and propitiate the Father. His death affected humanity by showing them God’s love, His hatred for sin, and was an example for how we should live. His death also affected the evil spirits of death, sin, Satan, and the demons by stripping them of their strength by the power of His blood. His death, first and foremost, affected God by propitiating His wrath, and paying the penalty for humanity’s sins. All of this was done simply so that we as humanity could once again share a relationship with our Father God and spend eternity with Him.