November 7

Concerning the directions given by Bahá'u'lláh for the recital of certain prayers, Shoghi Effendi wishes me to inform you that these regulations -- which by the way are very few and simple -- are of a great spiritual help to the individual believer, in that they help him to fully concentrate when praying and meditating. Their significance is thus purely spiritual. 
(From a letter dated 5 November 1934 written on behalf of Shoghi Effendi to an individual believer; The Compilation of Compilations, Vol. II, The Importance of Prayer, Meditation and the Devotional Attitude)