I think it's quite complicated anyway. We are using 'person' in a slightly different way. I am more saying person in and expanded sense of personhood. The trinity is three 'persons' in one. Also you are right there is a personification of God (the Father), you know bearded dude in the sky. Whereas Christian scripture states (afaik) that no one has seen the Father.
And obviously there are religions other than Christianity, which your question also asks about, but I'm not answering.
There's lots I don't know and still trying to learn:)