Islam , Christianity & Judaism all believe in a single God.
The argument seems to be the "method" you use to believe in God.
We all know 1 + 1 = 2
So what if we arrive at the answer by different means.
For some it may be (. + . = ..) for others
+
=
.
At the end of the day some people are good natured and some are bad natured .
I personally dont beleive in any religion (thats my choice) , I was brang up christian , but became disillusioned with the various religous groups (catholics , anglicans , baptists , metodist's and pentocostal's etc) all saying that thier particular brand of religion was the only way to get salvation.
I am an admirer of John Lennons words in the song "Imagine" " a world without religion"
If that happened thier would be a lot less death and suffering , through the numerous acts being committed currently in the name of religion.