August 26

Regarding your Bahá’í friend who does not fully understand the infallibility of the Manifestation of God: You should influence that person to study the matter more deeply, and to realize that the whole theory of Divine Revelation rests on the infallibility of the Prophet, be He Christ, Muhammad, Bahá’u’lláh, or one of the others. If They are not infallible, then They are not divine, and thus lose that essential link with God which, we believe, is the bond that educates men and causes all human progress. 
- Shoghi Effendi  (From a letter dated 11 January 1942 written on behalf of Shoghi Effendi to an individual believer, quoted by the Universal House of Justice in a letter dated 26 November 1986 to a National Spiritual assembly; ‘Messages from the Universal House of Justice 1986-2001)