Matthew 13:34-35:
All these things Jesus spoke to the multitude in parables; and without a parable He did not speak to them,This fulfilled what God had spoken through the prophet:
"I will speak to you in parables. I will explain things hidden since the creation of the world."
My flesh is true food and my blood is true drink.
It was believed until the time of Luther and the Protestant Rebellion. Why do you think it’s a cup of death of you do not discern the body and blood of our Lord?