He said he’d witnessed prominent tech figures taking drugs and arranging for sex (Mr. Epstein stressed that he never drank or used drugs of any kind)," Stewart wrote.
Stewart did not name anyone in particular and it is unclear whether Epstein told him any names.
Stewart said this 90-minute conversation was on background and could not be attributed to Epstein.
But Stewart said he determined that condition expired due to Epstein's apparent suicide in a Manhattan jail cell over the weekend.
Stewart said he sought an interview with Epstein to discuss whether he was advising Tesla and founder Elon Musk to find a new chief executive.
Tesla denies seeking Epstein's help, but Epstein told Stewart that he was considered "radioactive" and Tesla would deny that he had given advice if it ever became public.
Epstein said this stigma did not stop people from confiding in him and even told Stewart that he wanted to become a minister so that they could feel assured their disclosures would remain confidential.