I would suggest the problem lies with the word faith, as to how it is used to represent the eternal not seen in various parables.
2Co 4:18 While we look not at the things which are seen, but at the things which are not seen: for the things which are seen are temporal; but the things which are not seen are eternal.
Like many denominations that seek after a sign as that seen as their personal source of faith .The life of the flesh is in the blood but thre is no life in literal blood without the life of the Spirit. It returns to the lifeless spiritless dust and water as the clay God can form Christ in. We have the treasure in these earthen bodies but it is not of us if it is of God.
Men a hundred years ago accused a person of not having faith because he was given prescription glasses its the same the JWs perform as well as Catholicism to mention two I would think of that do it boldly
2Co 4:7 But we have this treasure in earthen vessels, that the excellency of the power may be of God, and not of us.
We are not to eat blood as a metaphor used to represent the spirit not seen it was to be poured into the ground to return where it came from just as Christ’s blood was used to show he had given born again spirit life in jeopardy of his own spirit as he gave up the Holy Spirit that returned to the father who gave it in the parable unless you do drink the blood of Christ it was used in respect to the spirit and not the flesh which Christ says profits for nothing. In a parable of David typfing the Son of man thirsting for the living water of the gospel in the Old Testament.
the well of Bethlehem, which is by the gate
I believe God helps to give us his understanding on what it means to drink blood. Which has nothing to do with literal blood transfusions
And David was then in an hold, and the garrison of the Philistines was then in Bethlehem.And David longed, and said, Oh that one would give me drink of the water of the well of Bethlehem, which is by the gate!And the three mighty men brake through the host of the Philistines, and drew water out of the well of Bethlehem, that was by the gate, and took it, and brought it to David: nevertheless he would not drink thereof, but poured it out unto the LORD.And he said, Be it far from me, O LORD, that I should do this: is not this the blood of the men that went in jeopardy of their lives? therefore he would not drink it. These things did these three mighty men. Sa 23:14