Eleazar Of Worms
There is a tradition that whoever knows the seventy six names of the angel Metatron can express any wish and see it fulfilled. The Book of Desire means just this: It teaches how to express a desire and call the related appropriate name of Metatron. Eleazar includes this small treatise after the two tomes concerning the Work of Creation and the Work of the Chariot in his Sodei Razia (lit. Secrets of Secrets, also called The Book of Raziel), which represent the two first kabbalistic levels. After a ritual purification, the apprentice can engage in the mystical meditations and call the proper name of Metatron. A proper preparation leads to the appearance of a Maggid, who is a messenger angel. This envoy, as Eleazar says, will appear "according to your will and as often as you desire". He will mediate between us and the superior worlds, taking care of fulfilling our wish through the power of Metatron.