I think it is because inevitably religion becomes a worldly entity. It is an organization, facing competition from other organizations, and being an organization depending on greater participation for it's survival. At that point, the focus moves from spiritual principles to power principles. That is where the shift occurs.

The inspirational stuff is still there, but the everyday workings of the church revolve around an entirely different agenda because it is an organization, essentially a business, that is dependent on income, participation, and popular support.

That is the difference.

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