I remember vividly what I remember reading when I read the Qur'an in the first chapter of the Exordium:

"In the name of God, the most compassionate the most merciful,

All praise is due to Allah, Lord of the Universe."

There are several reasons I can note  why we should believe in the existence of a Creator. Reasons could be such as: The complexity of life forms, the universe and its consistent laws, laws of planetary beings etc. But saving face it is perhaps also easily plausible to argue against that, but for the purpose of Interfaith dialogue I'd rather stay on the course of agreement here in the designer of the universe.

It is pretty much understood in the monotheistic tradition that there is One God and that, this God presides over the entire universe thus issuing the authority over ever being in existence. With this in mind we understand that from the sublunary world down to the world of man there are many complexities both within the macrocosmic and micrcosmic thus, without argument, this designer shows no favoritism to any life form. Even life forms whom we categorize at the bottom of the scale are essential to our own existence. For instance without plants whom use much of the world's carbon dioxide many living animals whom we know feed on plants who cease to exist, and ultimately we humans ourselves would cease to exist.

I could discuss the specifics of my argument but since I say much I will leave here that God is not specific to one religion. If he were it would be proven in the books of the prophets as well as in the Qur'an that there would be no evolution of religion.