Center of the Covenant
Baha'u'llah indicated in many ways the 'Abdu'l-Baha was to direct the Cause after His own ascension. Many years before His death He declared this in a veiled manner in His Kitab-i-Aqdas. He referred to 'Abdu'l-Baha on many occasions as "The Center of My Covenant," "The Most Great Branch," "The Branch from the Ancient Root." He habitually spoke of Him as "The Master" and required all His family to treat Him with marked deference; and in His Will and Testament He left explicit instructions that all should turn to Him and obey Him. (40:2)

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