After the rabbi narrowly escaped being burnt at the stake by the authorities in Westphalia who had charged him with sorcery, the German Count Alexander Leopold Anton von Rantzau secretly gave him refuge in Holzminden.

During this stay there in 1736, Falk made impressive kabbalistic performances in Rantzau's castle, witnessed by noblemen and the Count's son Georg Ludwig Albrecht.

[2] Rabbi Jacob Emden accused him of being a Sabbatean, as he invited Moses David of Podhayce, a known supporter of Sabbatai Zevi with connections to Jonathan Eibeschutz, to his home.

When Falk ran short of coal, he was said to have performed a magical feat involving three shirts and a ram's horn.

[citation needed] Some claimed that he had saved the Great Synagogue from fire by writing something in Hebrew on the pillars of the door.