BRIGHTON — The director of the office of healthcare ministry for the Archdiocese of Boston Jean Marchant resigned July 17 after revealing that she believes she was ordained a priest in a ceremony held in July 2005 on the St. Lawrence Seaway in Canada.

For the 2005 ceremony, Marchant adopted her great-grandmother’s family name, St. Onge, because at that time she was not ready to leave her ministry in the archdiocese, she said.

Marchant previously worked for five years as director of mission and spiritual care at Caritas Carney Hospital in Dorchester, and spent the 16 years previous in hospice ministry. She holds a master’s degree in divinity from the Weston Jesuit School of Theology in Cambridge and recently completed a doctorate from the Graduate Foundation in Indiana.

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