In Leviticus, before Christ’s time on earth, God gave his people specific instructions, otherwise known as law, on how to make him happy. For him to be happy, they needed to be perfect. To be perfect, they needed to be free from sin, completely, so he taught them how to obtain forgiveness of their sins through offering the sacrifice of animals in reverence to him.
In every sacrifice, there are three key elements that carry significance. The first is blood. In this case, only the blood of an animal would please God. No human sacrifices. Why did God choose to use blood to cleanse the sins of humans? In Leviticus 17:11 it says “For the life of a creature is in the blood.” The second element is a high priest. The people would bring their animals to a high priest so he could go to the Lord for them and offer the sacrifice. The third is a holy place, known as a tabernacle. The high priest would go into the holy place and sprinkle the blood of the animal on the alter and then burn the remains.
If all of it was done correctly, out of respect, the Lord would be pleased and would gladly forgive his people, but there was a problem. Using those methods, the methods written in law, didn’t make people perfect. Even after the sacrifices were made and God forgave them, the people were having trouble forgiving themselves. They were walking away with guilty consciences (Hebrews 9:9). God needed them to be guilt free, and God knew the law wasn’t good enough to make that happen.
What God did to fix the problem was install a new way of doing things with his people. It was called the new covenant, and the new covenant was no longer ruled by law but by the living Spirit of God. In other words, he brought his people closer to him.
The new covenant is basically a bulked up, more efficient version of the old practice of sacrificing animals. It uses the same three elements—blood, a high priest, and a tabernacle—but instead of sacrificing animals, God decided to sacrifice himself for his people. He was able to do this by putting his spirit into the flesh of a man. The spirit was known as the Son of God, and the man’s name was Jesus Christ.
Jesus did not go to a human high priest to offer himself as a sacrifice. He went directly to God–God the Father–and then God took the sacrificial offering into his own dwelling in heaven, making the tabernacle not man made but heavenly (Hebrews 9:11-12).
In conclusion, basically, what God did was take the matter of forgiving sin and repairing guilty consciences into his own hands. The only thing he leaves up to his people is the choice of whether they want to accept his sacrifice or not. If his people do accept Christ, “How much more, then, will the blood of Christ, who through the eternal Spirit offered himself unblemished to God, cleanse our consciences from the acts that lead to death, so that we may serve the living God!” (Hebrews 9:14).