Bifrons

The Forty-sixth Spirit is called Bifrons, or Bifröus, or Bifrovs. He is an Earl, and appeareth in the Form of a Monster; but after a while, at the Command of the Exorcist, he putteth on the shape of a Man. His Office is to make one knowing in Astrology, Geometry, and other Arts and Sciences. He teacheth the Virtues of Precious Stones and Woods. He changeth Dead Bodies, and putteth them in another place; also he lighteth seeming Candles upon the Graves of the Dead. He hath under his Command 6 Legions of Spirits. His Seal is this, which he will own and submit unto, etc.

As printed in Mathers’ Lesser Key of Solomon, page 45. The text above is that page’s, not a paraphrase of it.