A rak‘ah is the recitation of specifically revealed verses accompanied by a prescribed set of genuflections and other movements.
The Obligatory Prayer originally enjoined by Bahá’u’lláh upon His followers consisted of nine rak‘ahs. The precise nature of this prayer and the specific instructions for its recitation are unknown, as the prayer has been lost. (See note 9
In a Tablet commenting on the presently-binding Obligatory Prayers, ‘Abdu’l-Bahá indicates that “in every word and movement of the Obligatory Prayer there are allusions, mysteries and a wisdom that man is unable to comprehend, and letters and scrolls cannot contain.”
Shoghi Effendi explains1 that the few simple directions given by Bahá’u’lláh for the recital of certain prayers not only have a spiritual significance but that they also help the individual “to fully concentrate when praying and meditating.”
1 The Compilation of Compilations, Vol. II, , p. 237