Whoever says that eyes perceive Him has seen a likeness of Him.Whoever worships the Name and the Meaning has committed polytheism. Whoever describes Him by what occurs in his own soul has described himself. Whoever says He is veiled from His creation meant only other than Him. Whoever says He appeared to them such that they see Him has likened Him to an object of sight.
But whoever knows Him through the aspect of affirmation, and knows Him from where the miracles appeared, then denies what he saw [the physical form] and affirms what he knew [the Divine power]—those are the companions of the Commander of the Faithful (Amir al-Mu'minin), may his might be exalted."
And from Muhammad al-Karkhi, from Ismail b. Ali b. Sadaqa, from Al-Ridha—may his might be exalted—who said:
"Verily, that which you saw with your eyes of the form is Allah by its attribution to the Power 1. So, if the miracle appears from a person, the form is negated from him; for he whose form that is in reality is unable to manifest the miracle. And whoever manifests the miracle, that form is not his form; rather, it is the form of the helpless human."