Hello again, Mrs. A;
Rest assured your response is taken well; it’s fun talking with you.
Others have posted more since I’ve been here, showing some early sources that talk about the early Christian (Catholic) church, so I won’t tack those on. But one could look at the writings on the other beliefs of the Church in the early times, and lo and behold the beliefs are the ones that the Catholic church teaches today:
St. Ignatius (110 AD): They [heretics] abstain from Eucharist and from prayer, because they do no confess that the Eucharist is the Flesh of our Savior Jesus Christ…"
And regarding the Eucharist specifically, no doubt you’re familiar enough with the fact that the word “Trinity” is not in Scripture. Yet of course Christians believe in the concept. Even though Jesus didn’t say at the Last Supper, “Hey, I’m giving you this thing called Eucharist,” the word is simply the Catholic church’s way of describing what Jesus did do (Gk eucharistein, to give thanks). And to Protestants, the Eucharist may just be something “that Catholics do,” and we can talk about this for a good while. But it is noteworthy that it’s during the Last Supper that that was the only time in Jesus’ ministry that he mentions the covenant. As you know, the covenant is God’s way of swearing oaths with us and binding us all as (yep, you guessed it) one.