Anthimos Panagiotopoulos was born on December 25, 1943, in Patras, Greece. His parents were Spyridon and Angeliki Panagiotopoulos. In 1963, Anthimos was tonsured as a monk of Vatopedion Monastery. He graduated from the Anthonias Ecclesiastical Academy in 1964. Upon his ordination to the diaconate in late 1965, he served as archdeacon of the Metropolis of Patras, but later moved to Athens to enroll in the School of Theology of the University of Athens (from which he received a degree in 1973). While enrolled at the university, he served concurrently as deacon to the Athenian churches of St. Panteleimon and St. Spyridon.