To sum up, both His antagonists and His partisans, as well as all those who were received in the sacred spot, acknowledged and bore witness to the greatness of Baha'u'llah. Though they did not believe in Him, still they acknowledged His grandeur, and as soon as they entered the sacred spot, the presence of Baha'u'llah produced such an effect on most of them that they could not utter a word . How many times it happened that one of His most bitter enemies would resolve within himself, "I will say such and such things when I reach His presence, and I will dispute and argue thus with Him, " but when he entered the Holy Presence, he would become amazed and confounded, and remain speechless (34:2)

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'Abdu'l-Baha