Eleazar of Worms, Perush ha-Merkavah, MS Paris, BN 850, fol. 67a.

Jewish Mysticism
Commenting on the verse, ‘Upon this semblance of a throne, there was the semblance of a human form’ (Ezek. 1-26)-

The glory appeared to the prophets as a king sitting upon a throne. This is not to say that there is sitting [above] or any boundary to His unity. Rather, in order that the prophet may know who is speaking to him [the glory appears in this form]. Concerning this it says in the “Book of the Chariot” [i.e., the Shi‘ur Qomah] the measurement of the creator etc.

Translated by Elliot Wolfson in Through a Speculum that Shines- Vision and Imagination in Medieval Jewish Mysticism, Princeton- Princeton University Press, 1994.