Father John Mary Cioni, C.P., was born in Brandeglio (Lucca) on 7th July 1727. He entered the Passionist Congregation at the age of 18 and was educated by the Novice Master, Father Marcoaurelius Pastorelli, C.P., and by St. Paul of the Cross himself, to whom he often went for advice. Professed on 4th March 1747 he was a member of the first formal group of students under the direction of Fr. Marcoaurelius. As a Deacon he took part in the great mission preached in Camerino by St. Paul of the Cross and others.
He was Local Superior, Master of Novices, General Consultor and Provincial. St. Paul of the Cross chose him as his confessor after the death of Fr. John Baptist Daneo (1765), and sent him as Visitor when he was unable to make visitation. He entrusted him with the change of completing the foundation of the first monastery of Passionist Nuns in 1770-1771. Despite these various changes he was often involved in preaching missions, in writing memoirs of religious and the history of the Congregation, a large part of which in known through his writings.
The nine Passionists who gathered in Rome for the General Chapter in 1784 elected him the third Superior General of the Congregation.
He died on 7th February 1796 from a sickness contracted while hearing the confession of a patient with an infectious disease in the hospital of St. John.