“the glowing tribute paid to the Báb by the pen of Bahá’u’lláh”;” powerfully reinforced its character and elucidated its meaning” by ‘Abdu’l-Baha

However graphic the record which the eminent chronicler of His life [Nabil’s narrative] has transmitted to posterity, so luminous a narrative must pale before the glowing tribute paid to the Báb by the pen of Bahá’u’lláh. This tribute the Báb Himself has, by the clear assertion of His claim, abundantly supported, while the written testimonies of ‘Abdu’l Bahá have powerfully reinforced its character and elucidated its meaning. 

- Shoghi Effendi  (‘The Dispensation of Baha’u’llah; included in ‘The World Order of Baha’u’llah’)