A minor mistake on my part. In John 6:53 the word for eat is “phago”, which could be metaphorical. BUT, in the following verses, 54-58, Jesus ramps it up, and changes the word that is translated as eat to the Greek word “trogo”. Trogo’s meaning is not just eat, more specifically it is to gnaw on something, like a dog gnaws a bone. And in koine Greek, it is NEVER used metaphorically. The following is a link to an interesting article on that passage.
matt1618.freeyellow.com/trogo.html
And here is a quote from St. Irenaeus. The interesting thing about Irenaeus is that he was a disciple of St. Polycarp. And Polycarp just happened to be a disciple of some guy named John, who wrote some Gospel.
**“So then, if the mixed cup and the manufactured bread receive the Word of God and become the Eucharist, that is to say, the Blood and Body of Christ, which fortify and build up the substance of our flesh, how can these people claim that the flesh is incapable of receiving God’s gift of eternal life, when it is nourished by Christ’s Blood and Body and is His member? As the blessed apostle says in his letter to the Ephesians, ‘For we are members of His Body, of His flesh and of His bones’ (Eph. 5:30). He is not talking about some kind of ‘spiritual’ and ‘invisible’ man, ‘for a spirit does not have flesh an bones’ (Lk. 24:39). No, he is talking of the organism possessed by a real human being, composed of flesh and nerves and bones. It is this which is nourished by the cup which is His Blood, and is fortified by the bread which is His Body. The stem of the vine takes root in the earth and eventually bears fruit, and ‘the grain of wheat falls into the earth’ (Jn. 12:24), dissolves, rises again, multiplied by the all-containing Spirit of God, and finally after skilled processing, is put to human use. These two then receive the Word of God and become the Eucharist, which is the Body and Blood of Christ.”-“Five Books on the Unmasking and Refutation of the FalselyNamed Gnosis”. Book 5:2, 2-3, circa **