Faith.

To take the existence of the object of "the sacred", and/or "the holy", on gut feeling.

Gut feeling of course, being the basis for "the sacred", and "the holy", in the first place.

If you doubt it's just gut feeling, see the problems with "the transcendent", and "the supernatural".

(See this rant for a deeper contemplation on the subject)

(Also see "faith in faith")