When Jesus told His disciples to eat His flesh and drink His Blood, they left Him. To them and the culture they were in ... taught from childhood in their Jewish faith ... they didn't drink blood because this is where the life is. And they certainly didn't eat the flesh of anything that had died on its own. They had to kill the meat they ate and let the blood drain out before eating it.
What Jesus had said didnt make any sense to them. It went totally against their cultural learning ... the way they were brought up. So their response was: "This is a hard saying" ... "We don't receive this" ... "We are not cannibals". But Jesus didn't mean it that way. They didn't understand ... they couldn't ... at that time.
I think that Jesus said this for our benefit, so that we could see when we feed on His Word, we are feeding on His Body. The Word is His Body ... He is the Word.
The Gospel of John, chapter 1, verses 1 and 14a say "In the Beginning was the Word and the Word was with God, and the Word was God. And the Word was made flesh and dwelt among us, and we beheld His Glory as of the Only Begotten of the Father".
Reverend Robert W. & Mary C. Butler