If we are to look at this concept logically and think of the universe, one can argue that the right religion has to be monotheistic – meaning that it states there’s only one God. Islam is one example. 

As Allah says in the Qur’an,

“Had there been within them [i.e., the heavens and earth] gods besides Allah, they both would have been ruined. So exalted is Allah, Lord of the Throne, above what they describe.”

[Qur’an 21:22]

Here, Allah explains that if there were more than one God, there would be chaos and disorder in the world around us with gods disagreeing with or fighting one another. As good as each god may be, there is bound to be some conflict and it would show in the universe. 

At the end of the day, for the universe to run all its laws, you need one order dictating everything: a single end-cause. A lot of philosophy and science suggests that. Whether it’s a classroom, state, or country, you need one final voice. Now look at the picture above and think about the universe. How more important is one voice for that? 

Some may ask, “What if there is one God at the top and smaller gods under him?” However, you have to prove that. Whether it’s logically or by proving your religion right, you need to do that. Also, if there’s one supreme God that can do everything, that’s good enough and frankly solves many questions. That’s one philosophical argument behind monotheism. Lastly, even if there’s hierarchy within multiple gods, you would expect to see some issues in the cosmos as the Qur’an explains above and that would not be pretty!