I guess this is the kind of emotive trench warfare that I generally tend to avoid, but it was a question put to me honestly, I think, (over the Christmas sprouts) and so I began to think out a reply that was equally honest.
More of a discussion starter really.
But there are some points of logic that are irrefutable. Maybe that’s a good place to start:
The word “Monotheist” for example. As you’ll know, it means someone who believes in only one God.
So if monotheism, by definition, affirms that (ontologically speaking) there is one and only God over the entire universe, then no monotheist can accuse another monotheist of worshiping another God.
At most, they may accuse their fellow monotheist of improperly identifying the one God that both seek to serve.
The point is, no monotheist can hold, without contradiction, that more that one Supreme Being exists.This is what Kenneth Cragg means in The Call of the Minaret, when he points out that Muslims and Christians “are obviously referring when they speak of him, under whatever terms, to the same Being.”
The problem is not in identifying the ultimate referent of the word “God” but knowing how to respond to the wide range of predicates about God that sometimes seem contradictory.
I realise that, out here in the real world, such a point satisfies no one, because no Muslim or Christian that I have ever met worships a vague concept or a generic idea of “God.” No.
God is revealed (and worshipped) in what he has said and done.
As any monotheist will acknowledge.
But even if this one tiny bridge of logic is accepted, then it is possible that a conversation may begin.