It isn’t about cruelty to animals, or blood sausage or whether we can order a medium rare steak. Those subjects completely miss the point.
It’s about the Eucharist.
The prohibition against the consumption of blood was about the perfect blood of Christ which was to come. The prohibition against the consumption of blood is about the Eucharist. Christ’s flesh is
true food, and his blood is
true drink, and unless you eat his flesh and drink his blood you
have no life in you.
Only be sure that you do not eat the blood; for the blood is the life, and you shall not eat the life with the flesh. (Dueteronomy 12:23)
Consuming the blood of an animal is allegorical, symbolic of living the life of an animal. The life of an animal is its blood. The pagans of the Old Testament lived like animals. God doesn’t want us to live like animals. God want’s us to live the eternal life of Christ, and so that’s why drink the blood of Christ, because the “The blood is the life.”
Jesus said to them, "Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. Whoever eats my flesh and drinks my blood has eternal life, and I will raise him on the last day. (John 6:53-54)
The prohibition against consumption of blood is less about blood than it is about life, and which life the Jews chose to live - the life of an animal or the life of God? God was telling them not to live like animals until the messiah came, and then they would consume the messiah’s blood, and they would be given divine life.
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-Tim-