Judah Leib (Leibele) (Löbele) Prossnitz (c. 1670 – c. 1730/1750) was a kabbalist born about the end of the seventeenth century at Uherský Brod, Moravia.
He left his native city and went to Prostějov (German: Prossnitz), Moravia, where he married, earning a livelihood by peddling in the neighboring villages.
One night he promised to summon the Shekhina to appear at midnight at a large gathering.
Prossnitz stretched across his room a perforated curtain, behind which he had secretly lighted a mixture of alcohol and turpentine.
Robed in white, he stood behind the curtain, and the light brought out in full relief the gilt letters of the Tetragrammaton, which he had placed on his breast.