Appearing on the US version of Who Do You Think You Are, the actress, who is married to British rocker Chris Martin, discovered her great-great-granddad Simon Paltrovich.
She was told his dad was also a rabbi – and according to a memorial book by Holocaust survivors from his Polish community, he had incredible powers.
The book said he was “a great holy man and master of Kabbalah” and told of a fire that erupted in the town and was heading towards the Jewish neighbourhood.
Reading from a translation, Paltrow said the rabbi “went out to the balcony of his house, waved his handkerchief towards the fire and the fire was extinguished”.
The actress, who also studies Kabbalah, said: “This is all blowing my mind.”