Father Joseph Mammis was born on August 19, 1972 in Montreal, Canada by parents who had emigrated from Greece. He received his general education in Montreal and is fluent in three languages. After graduating from high school, he went on to receive his degree in Athletic Therapy from Concordia University which included a two year internship in clinical work. His daily life as a student included politics, athletics, and involvement as an active member of the Greek Orthodox Community in Montreal. He then entered the monastic life in 1995, at the monastery of St. Anthony in Florence, AZ, and was tonsured a monk in November of 1996.
On January 16, 1997, he was ordained to the diaconate by the late Metropolitan Anthony of San Francisco. Then, in August of 1998, he and another monk were asked to help establish the monastery of Holy Trinity in Smiths Creek. MI. Father Joseph was ordained to the priesthood at the Holy Monastery of the Archangels in Kendalia, TX on November 4 1998, by then Archbishop of America Spyridon, and was appointed Abbot of Holy Trinity Monastery in Smiths Creek, MI. He has since served as abbot and spiritual father of the community, which now includes a brotherhood of nine.