September 26
Saints Cosmas and Damian is invoked as patron of surgeons. Cosmas and Damian, traditionally said to be twin brothers, were Arab Christians of the late third century who practiced medicine without payment and were known therefore as the Anargyroi, the silverless ones. Their cultus is securely attested from the fifth century: a great basilica was built in their honor at Cyrrhus in Syria, where their relics were translated; another, founded in their memory at Constantinople by the Emperor Justinian (527-565), became one of the chief churches of the Byzantine capital. Sources: https://www.vatican.va/content/john-xxiii/la/motu_proprio/documents/hf_j-xxiii_motu-proprio_19620713_rubricarum-instructum.html.