A statue of St. John Cantius was most probably made during the creation of the high altar, before 1747. It is probably the work of sculptor Antoni Gegenbaur. It was only later joined together with a reliquary. Saint John Cantius studied at the Cracow University, where he obtained a master's degree in theology and then he lectured there. He is considered one of the best Polish saint scholars.
Paulina Kluz, "St. John Cantius", [in:] "The Sacred Lesser Poland Heritage", 2021, source: https://sdm.upjp2.edu.pl/en/works/st-john-cantius