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Eventually, studies for the priesthood led Hilary to St. Charles College in Ellicot City Maryland, then to the old St. Mary, Our Lady of the Lake Major Seminary on Cleveland’s Lakeshore Avenue for two years before being sent to the American College in Rome. He was ordained a priest for the Diocese of Cleveland at the Lateran Basilica in Rome by Cardinal Pompili, the vicar general of Rome, on May 17th, 1913. His first Mass was held the next day at the Tomb of Saint Peter.
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On the 6th of July 1928 with just fifteen years of priesthood under his belt, Fr. Zwisler became the founding pastor of St. Sebastian Parish. Not until the priest shortages of the early twenty first century were such young men made pastors in this diocese, let alone founding pastors.
Father Zwisler arrived back in Akron on the 7th of July and took up residence in the newly constructed St. Thomas Hospital named after Fr. Thomas F. Mahar who was pastor of St. Vincent Parish for 34 years. His first order of business was determining exactly what his parish boundaries would be. Fr. Zwilser met with the pastor of St. Vincent Parish, Fr. John J. Scullen, from whose territory the new parish was to be formed. The dividing line between the two parishes would be Portage Path and Diagonal Road from Botzum to Wooster Avenue. The Southern boundary would be Wooster Avenue, the Cuyahoga River to the north, and finally to to the west it would extend out toward Peninsula, Medina, and Wadsworth. At the time the area known as Wallhaven was considered the very edge of the city and the roads from that point out to these towns were little more than dirt and the only civilization farms.
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