Baha'u'llah's source of knowledge

"We purposed to read some of his works. Although We never felt disposed to peruse other peoples’ writings, yet as some had questioned Us concerning him, We felt it necessary to refer to his books, in order that We might answer Our questioners with knowledge and understanding. His works, in the Arabic tongue, were, however, not available . . . We sent for the book, and kept it with Us a few days. It was probably referred to twice,”

(Baha’u’llah, The Kitab-i-Iqan, pp. 184–186.)