The second of five in the series, and the first in the "core". And the very first is simply: To Dare.
From the time our spiritual life gets beyond rote recital of prayers of the "Now I lay me down to sleep" variety, most of us try to find a spirituality that works. It works, and preferably it has deities (or a deity) who do something more than keep score on us.
To get there, it is necessary to try going there. And, as we've often said, what works for someone else might not be appropriate for you.
Of course, there will always be the self-appointed theologians who will try to take control of your spiritual life. If you know the basic boundaries and you are getting to know what works for you, you will (hopefully) be able to know the difference between help and manipulation.
To Dare - To Know - To Will - To Keep Silence are the four basics, but there is a reason why "To Dare" is the first of the list!