Religion is occult.
oc·cult
-adjective
1. of or pertaining to magic, astrology, or any system claiming use or
knowledge of secret or supernatural powers or agencies.
2. beyond the range of ordinary knowledge or understanding; mysterious.
3. secret; disclosed or communicated only to the initiated.
4. hidden from view.
5. (in early science)
a. not apparent on mere inspection but discoverable by experimentation.
b. of a nature not understood, as physical qualities.
c. dealing with such qualities; experimental: occult science.
6. Medicine/Medical. present in amounts too small to be visible: a
chemical
test to detect occult blood in the stool.
-noun
7. the supernatural or supernatural agencies and affairs considered as a
whole (usually prec. by the).
8. occult studies or sciences (usually prec. by the).
-verb (used with object)
9. to block or shut off (an object) from view; hide.
10. Astronomy. to hide (a celestial body) by occultation.
-verb (used without object)
11. to become hidden or shut off from view.
[Origin: 1520-30; < L occultus (ptp. of occulere to hide from view, cover
up), equiv. to oc- oc- + -cul-, akin to célare to conceal + -tus ptp.
suffix]