On 2 July 1505, while Luther was returning to university on horseback following a trip home, a lightning bolt struck near him during a thunderstorm. He later told his father that he was terrified of death and divine judgment, and he cried out, “Help! Saint Anna, I will become a monk!” He came to view his cry for help as a vow that he could never break.
Diocese (Wikipedia) In church governance, a diocese or bishopric is the ecclesiastical district under the jurisdiction of a bishop.