I can't understand the Protestant interpretation of John 6. In your opinion, is there anything true in the Catholic Church's teachings today? It is making some outlandish claims, notably that you will hear Christ speak through her today, especially on issues where the Bible is silent, i.e. contraception, stem-cell research, and the claim that it has the fullness of truth (1 Timothy 3:15). I have not heard that from any other Church so far. So it is extremely wrong or it is extremely right. Last, if you came to believe that all that the Catholic Church taught was true, would you join it?
Yes, I have read a lot of church history. If we literalize such passages as John 6, why not be consistent and say that the cup is the new covenant (Luke 22:20; 1 Corinthians 11:25)? To my knowledge, no Catholic says this! (They may say the words in their liturgy, but I am unfamiliar with the theology that has a chalice transubstantiating into a covenant.) The doctrine of transubstiation does not work, even though many of their teachings are biblical.
And yes, if I thought the Catholics were on the right track, I would most certainly join them. But I see the result of sixteen centuries of drifting from the word of God. Had I been in charge -- who knows! -- we might have drifted much farther. I certainly do not mean to insinuate insincerity. This is about truth, not about one's favorite denomination. It comes down to what the New Testament says about the church of Christ.