The belief of a higher order being can bring about a sense of peace of mind that someone higher above is watching over you in addition to the belonging that one can find in like-minded crowds/gatherings.

This historical collection of beliefs in combination with any random person calling themselves a priest/bishop/evangelist means that people will follow whomever like sheep because they want that security even if built on fragile scaffolding.

Unfortunately as this system can create a large quantity of easily exploitable people; you’ll see many corrupt governments, corporations, and cults try to replicate this in order to milk people for all their worth even at the expense of literally everything good in the world.