You're VERY religious, if you ask me. Just not my religion- perhaps your own?
A person by
our definition is someone you can have a relationship with. Someone who loves, and who can be loved, for example.
Now, the scriptures teach that you can have a relationship with God the Father, as this is re-iterated over and over again in the OT.
Likewise, you can have the same with Jesus Christ. Likewise the Holy Spirit.....
2Co 13:14 May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all. Amen.
This text, exegeted and
not interpreted, states: a) Jesus is Lord (κύριος

and He gives grace (an act only God can perform) b) God gives love and c) the Holy Spirit gives fellowship. If the Holy Spirit is not a person, He cannot give fellowship. If Jesus is not a person, then He cannot give grace, and if God is not a person He cannot love. But because they can give grace, fellowship and love they are persons. Three persons, yet the scriptures declare that there is only One God.
There you have it. Simple. I'm sure your theology will complicate this very simple, very accessible thought, but no Christian theology has ever, ever claimed that a "person" can
only be a human being. You are mis-understanding Christian theology, and that's a shame because I can pull out any one of several Christian theological tomes across the denominations that clearly state and agree upon what personhood means in relation to God and man. You're mistaken about us and our beliefs.
Also, you ask for a text that says "God is three persons"- and we can show that this text above has no other meaning when read plainly for all to see.
However, I hope you're not just playing semantic games with me, as all I have to do is say that "show me in the Bible where it says there can be a such thing as a Christian Universalist", and of course the answer is "no text says exactly that", yet I know that you came to that belief because you took many texts together. This is your practice, and you must allow it to your fellow posters. Our theology is a result of centuries of prayer and reading. We can prove it's very ancient roots, even pre-dating the canon of scripture. You might want to be a little more respectful of our heritage and even the intelligence of those who came before both of us. You don't have to agree, but at least see that it's not just some bizzare tradition invented by some person know one can name or put a date to (which would be a conspiracy theory).
As I mentioned above, the church does not teach that a person is a always only a human being. This is why you misunderstand the Trinity from the start, it appears. You're arguing that we teach that the Trinity is three human beings, when it is blatantly obvious that this is not true.
Secondly, when exactly did the "Catholic Church" "come along" and who started it? What was his name, what day was it and let's see the foundational documents, first meeting, and all that. Even the church historians haven't been able to produce that documentation. Furthermore,why was there no outcry if new teachings were introduced into the church? We all know that the early Christians were terribly intolerant of new teachings. We know that they were outraged when Arius taught against the Divinity of Christ, and investigations show that he was bringing the new doctrine, not the Nicean Fathers. The fact is- the church is the church is the church. According to the scriptures. Founded by Christ, given to the Apostles, who passed its care to other overseers in an unbroken line of teachers and teaching. It's never ended, it's never going to. It exists.
Well, pardon my reflecting back at you but if I was as judgmental as that I could say "perhaps it's departed you". I know God's glory is amongst us- I've seen it first hand- even despite our sins. I can't imagine why anyone would pick a moniker for such hostile reasons, not to mention it really conjures up a image that perhaps isn't really what you're about? I certainly took it to represent a person who left the church to start his own religion or something.