There are four gate-keepers at the entrace to the Realm of Freedom [moksha].
Self control
Spirit of Inquiry
Contentment
Good Company
With a pure heart and a receptive mind, and without the veil of doubt and restlessness of the mind, listen to the exposition of the nature and means of liberation.
Sage Vasishtha
Source: The Concise Yoga Vasistha, Pages: 29
Contributed by: Meenakshi