They [Bahá'u'lláh and 'Abdu'l-Bahá] have also, in
unequivocal and emphatic language, appointed those twin institutions of the
House of Justice and of the Guardianship as their chosen Successors, destined
to apply the principles, promulgate the laws, protect the institutions, adapt
loyally and intelligently the Faith to the requirements of progressive society,
and consummate the incorruptible inheritance which the Founders of the Faith
have bequeathed to the world.
(Shoghi
Effendi, from a letter of 21 March 1930, published in ‘The World Order of
Bahá'u'lláh - Selected Letters’; The Compilation of Compilations, vol. I, The
Covenant)