Causes Of Relevance Of Religion
This is the starting point that Ghamidi saheb pointed out. The rest is details, and many other aspects can be added to it. Sense of being created is essentially and originally makes man think of his creator. Pint three is covered in the above answer. Yes, this is metaphysics which makes an idea a religion, technically, however, this metaphysics should come as news or revelation from the metaphysical world, not self-conceived or self-discovered, as it is the case with Buddhism and Sufism.