Someone might ask, with great feeling, and who are you, "Father Fox, to make these rules?"
My answer: I'm nobody: I didn't make these rules. These originate from the very beginning of the Church (see earlier post). I might just as easily ask you, who are you to RE-make them?
Again, this discussion is often about how terrible "barriers" and "rules" are. Which raises the question -- or two questions (which I'd really like to ask those who sincerely object to this ancient practice of Catholics and other ancient Churches):
1) What rules should there be? Any at all?
2) And who makes them?
You don't like the Catholic Church saying you must be Catholic (Orthodox are allowed too, see Code of Canon Law 844, and there are some other, very rare exceptions) and not in mortal sin. So what should the rule be?
(Waiting for the answer. Waiting....waiting...waiting.)
There could be a thousand different answers, but they all come down to one of two options: either absolutely anyone can receive the Eucharist...or else, there are some limitations, some person or species to whom the answer is, "Sorry, but no."
And if you think there should be some limit -- or else you believe Muslims, Hindus, atheists can all come to communion -- then why are Catholics terrible for drawing a line with one breath; but with the next, drawing the line is suddenly OK? Why is your line-drawing so much better than that of the early Church, which the Church continues (with, let us be candid, far less rigor)?
So, of course, this leads to the second question, which is, who decides these things? And the Catholic answer is, well, not you; and not me.
I started simply to say that the Magisterium decides, and that's mostly-but-not-exactly true; that might imply that the bishops could do what they like; and that's certainly not true. That's why I have emphasized all along that the Church is continuing what the early Church did. If you asked Pope Francis, or any of the bishops, whether they could just decide, tomorrow, that it was time to jettison the long-standing Eucharistic discipline, they would all say, no, that's not simply up to them. It's a complicated question, because we must be faithful to the Apostolic Tradition; we hand on faithfully that which was handed on to us.
Indeed, this is precisely how Saint Paul talks about the Eucharist:
For I received from the Lord what I also handed on to you, that the Lord Jesus, on the night he was handed over, took bread, and, after he had given thanks, broke it and said, “This is my body that is for you. Do this in remembrance of me.” In the same way also the cup, after supper, saying, “This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me" (1 Corinthians 11:23-25).
Again, forgive me for putting it baldly, but again I ask: who died and made you boss? Why do you get to set the rules? It's not a rhetorical question. If there are rules, someone must make them, right? Why shouldn't the Catholic Church make the rules for Catholic sacraments?
Look, I am inspired to see other Christians drawn to the Eucharist, and I want you to have what you want. But we don't ever get to come to God and say, God, I want you on my terms, not yours.
If you are coming to a Catholic Mass (wonderful! welcome!), and you find yourself wanting to receive the Eucharist, instead of short-circuiting your reflections into, oh how terrible it is that ____ (Pope Francis/"the bishops"/this priest) won't let me have communion, maybe instead ask yourself, why is it so important to me that I receive this sacrament, here? What does this mean to me? What does it mean to these folks around me?
If you want to share in the Eucharist with Catholics, are you prepared to know exactly what the Eucharist means to Catholics? Don't you think this is a fair thing to consider? Surely you don't think of the Eucharist as a "freebie" that anyone can take? You understand this is central to the entire Catholic Faith? Have you considered that maybe you haven't yet begun to understand what "sharing the Eucharist with Catholics" even means? And if that's true...why shouldn't you wait?