There are only 2 core religions, though the first is not truly a religion as it has no set doctrine, nor a list of commandments bar one. This is the belief that there is a spiritual power, gods, more than 1, polytheism, whatever you want to call it. All ancient civilisations practised this sort of belief, that gods existed and that mankind should seek knowledge of these gods.
The second form of religion is monotheistic, that there is only one God, a religion that through history has practiced suppression on the other form. It's doctrine is that mankind should have faith and believe, but that anything beyond this is a mystery and should remain so, with prescribed punishment for those who disobey.
The first, acknowledges the existence of the God of the second, describing him as a jealous God, the God of War, a God who claims to be the only God. This God and the various religions that follow him appear to be totally divided, with a history of waring among themselves, continuing today. A policy of divide and rule, too busy waring among themselves to seek an alternative. And also forbidden to do so.
Consider the story of Adam and Eve, forbidden to eat from the Tree of Knowledge. But what is wrong with knowledge? Knowledge is truth and the truth will set you free. So why should a God, who claims to be the one and only God, fear mankind knowing the truth? Unless he is not what he claims to be.