Procopius of Ustyug (Russian: Прокопий Устюжский) or Procopius of Lübeck (Russian: Прокопий Любекский; German: Prokop(ius) von Ustjug und Lübeck; died (1303-07-08)July 8, 1303)[1] was a fool for Christ (yurodivy) and miracle worker, formerly a merchant from Lübeck.

Though he is sometimes identified as one Jacob Potharst, son of a Lübeck merchant, Procopius' worldly name, surname, date and place of birth are not reliably determined.

[2] Born in Lübeck, Germany, he was a Roman Catholic merchant who converted to Eastern Orthodox Christianity during his travels.

In 1290, he predicted the fall of a meteorite near Veliky Ustyug, as well as tornado and conflagration.

[4] The incorrupt relics of St. Procopius were discovered in the 18th century near the Entrance of the Theotokos to the Temple Church in Veliky Ustyug and placed in the church, where they remained in open view for two hundred years, being the putative source of numerous healings.