I remembered, a few moments ago, that this was actually something I meant to mention in the oaths and anthems post a few days ago, but I overlooked it when I was writing the part about the Lord's Prayer and how there've been the two different versions in my life; my personal preference being for the fuller, Protestant version.
I was thinking, the other day, of the Lord's Prayer... specifically, the wording of it, and its ecumenical applications. A strange thing for a supposed atheist to dwell on, I guess, but there it is. I was trying to work out if there's anything, aside from its general association with Christianity, that disqualifies it from use in other Abrahamic faiths. I mean, is there anything in the wording of the prayer itself that would make it obnoxious to the tenets of either Judaism, or Islam?
Obviously, I'm no expert. But it seems to me to be a strong candidate. It makes no mention of Jesus or the Holy Ghost, and implies nothing about the Trinity. It speaks of God only as "our Father". That might be strictly a New Testament usage. I don't know if it's a relationship that finds expression in Judaism or Islam. I'm inclined to think it's probably not a problem in Judaism, but I know Muslims have a very strong concept of God as very different from his creation, and the idea of him having a "son" is repugnant to them. So I'm less sure that referring to God as "our Father" would sit well with them. Nevertheless, I don't know.
But generally, it seems to me the prayer ought to have a fairly universal applicability in monotheist faiths.