Einstein was not a big supporter of organized religion. Certainly not a supporter of organized religion having a strong role in society, which in mind would no doubt be tied up with so many inevitable issues relating to prejudice and injustice.

But he was not an atheist. He believed in a sort of cosmic, impersonal God. Not a big guy in the sky with a beard who would listen to you when you prayed and grant wishes or make sure there was enough fish and bread for your party or whatever. Einstein's God was indistinguishable from the universe itself — the order of the universe was God. So he was what we might call a pantheist (God is everything), or a Spinozan deist (God is absent order).

As you can readily appreciate this is not a view of religion that lends itself to organization, much less having a strong role in society. For him, the study of science was the ultimately most supremely religious activity, because to understand the universe was to understand God.