Guide for the Perplexed, by Moses Maimonides, Friedländer tr. [1904], at sacred-texts.com
IT might be thought that the Hebrew words temunah and tabnit have one and the same meaning, but this is not the case. Tabnit, derived from the verb banah (he built), signifies the build and construction of a thing--that is to say, its figure, whether square, round, triangular, or of any other shape. Comp. "the pattern (tabnit) of the Tabernacle and the pattern (tabnit) of all its vessels" (Exod. xxv. 9); "according to the pattern (tabnit) which thou wast shown upon the mount" (Exod. xxv, 40); "the form of any bird" (Deut. iv. 17); "the form (tabnit) of a hand" (Ezek. viii. 3); "the pattern
[paragraph continues] (tabnit) of the porch" (1 Chron. xxviii. 11). In all these quotations it is the shape which is referred to. Therefore the Hebrew language never employs the word tabnit in speaking of the qualities of God Almighty.
The term temunah, on the other hand, is used in the Bible in three different senses. It signifies, first, the outlines of things which are perceived by our bodily senses, i.e., their shape and form; as, e.g., "And ye make an image the form (temunat) of some likeness" (Deut. iv. 16); "for ye saw no likeness" (temunah) (Deut. iv. 15). Secondly, the forms of our imagination, i.e., the impressions retained in imagination when the objects have ceased to affect our senses. In this sense it is used in the passage which begins "In thoughts from the visions of the night" (Job iv. 13), and which concludes "it remained but I could not recognize its sight, only an image--temunah--was before my eyes," i.e., an image which presented itself to my sight during sleep. Thirdly, the true form of an object, which is perceived only by the intellect: and it is in this third signification that the term is applied to God. The words "And the similitude of the Lord shall he behold" (Num. xii. 8) therefore mean "he shall comprehend the true essence of the Lord."