God could have chosen any way to forgive humanity, but He linked forgiveness with blood because blood is costly. He could have asked us to chop down a tree to be forgiven, but He didn't. He chose blood because He likes that imagery. He is a God of story and wants to change our hearts through that story.
He chose blood to be the price of sin. This is all throughout the Old and New Testament. The blood sacrifice brought about forgiveness. Forgiveness is the point of sacrifice. Jesus' death on the cross is the point of forgiveness for all mankind because Jesus was the perfect, sinless sacrifice. He was the end to sacrifice. All sacrifices up to that point were not perfect; His sacrifice was. Our sin is covered through that sacrifice when we have faith and surrender our lives to God.
Now, if we turn around and continue to live in sin, that forgiveness is meaningless. The sacrifice still has meaning, and the forgiveness is there to be taken. Nothing can take diminish the value of that sacrifice. It is priceless and cannot be purchased. But if we do not surrender our lives, then it cannot be attained by us. The price is death. His death. And our death to ourselves.
However, there is grace in that sacrifice, for we do not have to be perfect. We still sin, and the sacrifice covers our sin.
The sacrifice covers the sin of all in the kingdom. It is as if when we walk into the gate of the kingdom of God, the blood of Jesus is poured on us, washing all our sins away. We are then pronounced perfect despite not being completely sanctified. We are God's people now, clothed in His blood.
Sounds kind of morbid. But it's just an illustration. Blood is costly.
The resurrection, the Church, and the Holy Spirit all play a part in us being the citizens in that kingdom. For in the outland we were dead and dying. But the resurrection shows us that in the Kingdom we have life. In the outland, we were living for ourselves. In the Kingdom, we have the Holy Spirit in us, guiding us. In the outland, we were not a people, but in the Kingdom we are the Church. His people. His hands and feet. His life.
Let's learn to live surrendered lives together in the glory of His Kingdom.