March 18

...There are no set forms of meditation prescribed in the teachings, no plan, as such, for inner development. The friends are urged - nay enjoined - to pray, and they also should meditate, but the manner of doing the latter is left entirely to the individual...

The inspiration received through meditation is of a nature that one cannot measure or determine. God can inspire into our minds things that we had no previous knowledge of, if He desires to do so. 
- Shoghi Effendi  (From a letter dated January 25, 1943 written on behalf of Shoghi Effendi to an individual believer; compilation: ‘Lights of Guidance’)