The subject is discussed in a number of places throughout The Priceless Pearl, op. cit. See particularly pages 79, 85, 90, 128 and 159.
Tablets of Bahá’u’lláh revealed after the Kitáb-i-Aqdas, op. cit., p. 69.
‘Abdu’l-Bahá, The Secret of Divine Civilization, op. cit., pp. 96-97.
J. E. Esslemont, Bahá’u’lláh and the New Era: An Introduction to the Bahá’í Faith, 5th rev. ed. (Wilmette: Bahá’í Publishing Trust, 1998), p. 250.
Will and Testament of ‘Abdu’l-Bahá, op. cit., p. 11.
Shoghi Effendi, The World Order of Bahá’u’lláh, op. cit., p. 8.
Bahá’u’lláh, The Kitáb-i-Aqdas, op. cit., paragraph 83.
Bahá’u’lláh, Epistle to the Son of the Wolf (Wilmette: Bahá’í Publishing Trust, 1988), p. 14.
Shoghi Effendi, The World Order of Bahá’u’lláh, op. cit., pp. 43, 195.
ibid., p. 24.