The Reason Why Abstaining From Blood Is So Vital (Leviticus 17:11-12).
“For the life of the flesh is in the blood, and I have given it to you on the altar to make atonement for your persons. For it is the blood that makes atonement by reason of the life.”
And the reason for this provision, which was permanent and binding, and permitted of no exception, was because ‘the life of the flesh is in the blood', the blood uniquely represents the life. It was the life principle of the animal, and no human being should seek to partake of an animal's life principle. It belonged solely to God.
But God had in His goodness provided that that life principle might be laid out in death on the altar in order to make atonement for the people. The life of that part of creation that God had provided as food for men, and as suitable for sacrifice, was offered in lieu of the lives of the sons of men. For the blood atones precisely because it represents the life laid out in death. Such continual sacrifice resulted in continual substitution for, and atonement for, sin, as the death of others provided by God was in this way constantly used to purify the sin of Israel and atone for it.
“Therefore I said to the children of Israel, No one of you shall eat blood, neither shall any stranger who sojourns among you eat blood.”
That is why no permanent resident of Israel, whether homeborn or sojourner (permanent alien resident) would be permitted to partake of blood. The blood was the life of the animals, could only be given to God in death, was laid out in death for man's sins, and was the sacred symbol of God's atoning work. It was thus not available for man's use.
So constantly the people of God had the reminder of their own sin, and of the death which was the consequence of sin, and of the atonement that God had made available for them, in each domestic animal that was slain. So too must we daily and continually remind ourselves of the One Who was slain for us, that we might be forgiven and find reconciliation with God, and live out our lives to please Him.