Today, Catholics celebrate Corpus Christi, celebrating the real presence of the body and blood of Jesus Christ, the Son of God, in the Eucharist—known as transubstantiation. [Wikipedia]. When saying “Truly, truly, I say to you, unless you eat the flesh of the Son of ma n and drink his blood, you have no life in you; he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. For my flesh is food indeed, and my blood is drink indeed. He who eats my flesh and drinks my blood abides in me, and I in him” (John 6:53–56), Jesus didn’t then follow that up with “Psych!” He didn’t say that he was just joking, or that he was talking figuratively, or anything like that. While hundreds of his followers walked away, he didn’t yell out “Just kidding! Come back and I’ll explain!” For over 1500 years, Christians knew that Jesus wasn’t talking symbolically.
Here’s a great article on this topic: https://www.catholic.com/tract/christ-in-the-eucharist Enjoy!