There is, for example, the Greater Covenant which every
Manifestation of God makes with His followers, promising that in the fullness
of time a new Manifestation will be sent, and taking from them the undertaking
to accept Him when this occurs. There is also the Lesser Covenant that a
Manifestation of God makes with His followers that they will accept His
appointed successor after Him. If they do so, the Faith can remain united and
pure. If not, the Faith becomes divided and its force spent… It is a Covenant
of this kind that Bahá'u'lláh made with His followers regarding 'Abdu'l-Bahá, and
that 'Abdu'l-Bahá perpetuated through the Administrative Order that Bahá'u'lláh
had already created.
- The Universal House of Justice (Letter from the Universal House of Justice, dated March 3, 1975, to an individual believer; Developing Distinctive Baha’i Communities, NSA of USA, 1998 edition)