Leviticus 17:12 Therefore I said unto the children of Israel, No soul of you shall eat blood, neither shall any stranger that sojourneth among you eat blood.
The reason for this command is in v. 11: “The life of the flesh is in the blood…it is to make atonement for the soul.” To shed the blood of a sacrificial animal is to remove its life. The shed blood of the sacrificial lamb is a substitutionary death in place of the one who brings the sacrifice. The judgment for sin is death. The soul that sins must die.
All of these blood sacrifices obviously point to the once-for-all blood sacrifice of the Lamb of God. And the prohibition against eating blood was rescinded when the fulfillment came true. Now Jesus says, “Unless you drink the blood [of the Son of Man] you have no life in you.” We eat the flesh and drink the blood of Christ every Sunday. And we have life, for life is in the blood. In fact, Jesus gives us the life of God, eternal life
We do not eat the blood, as Satanists do, for that would be making a mockery of the blood of Christ in Communion. In fact, we respect the Blood since life is in it. We partake of the blood of Christ by believing in Him. By faith we have life, the life of God. We do not respond to the mercy of God by any kind of magic rite to make something happen, but by receiving it with faith. Therefore, we do not eat blood to please God or earn God’s favor. We do drink the blood of Christ in Communion because we have already received mercy.