In the Name of Allah the Merciful, the Compassionate, Who manifests Himself through everything, the revelation of a clear knowing to whomsoever He wishes, peace be upon you, my son. This praise belongs to Allah Who manifests Himself on the head of a pin to whom He wishes, so that one testifies that He is not, and another testifies that there is none other than He. But the witnessing in the denying of Him is not rejected, and the witnessing in the affirming of Him is not praised.

As quoted in "Husayn ibn Mansur al-Hallaj" at Sidi Muhammad Press