The opening chapter of Iamblichus on The Mysteries, translated by Taylor from the Greek in 1821, is devoted chiefly to showing that true inspiration has but one source, however various the channels.
"Hermes, the God who presides over language, was formerly very properly considered as common to all priests; and the power who presides over the true science concerning the Gods is one and the same in the whole of things. Hence our ancestors dedicated the inventions of their wisdom to this deity, inscribing all their own writings with the name of Hermes. If, therefore, we participate in a portion of this God, adapted and commensurate to our powers, you do well to propose your theological doubts to the priests as friends, and to make those doubts known to them. I also very properly conceiving that the epistle sent to my disciple Ambo was written to me, shall give you a true answer to your inquiries. For it would not be becoming that Pythagoras and Plato, Democritus and Endoxus, and many others of the ancient Greeks, should have obtained appropriate instruction from the sacred scribes of their time, but that you who are our contemporary and think conformably to those ancients, should be frustrated of your wish by those who are now living and who are called common preceptors. I therefore thus betake myself to the present discussion; and do you, if you please, conceive that the same person to whom you sent the letter returns you an answer. Or, if it should seem fit to you, admit it to be me who discourses with you in writing, or some other prophet of the Egyptians, for this is of no consequence.
"Or, which I think is still better, dismiss the consideration whether the speaker is an inferior or superior character, but direct your attention to what is said, so as readily to excite your mind to survey whether what is asserted is true or false."
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