Almost nothing is known of his early life, but we do know that Saint Paphnutius was an Egyptian and follower of Saint Anthony the great. After many years of studying and discipleship , he was elected bishop for the Upper Thebaid region.
When Maximinus Daia began his persecution of Christians in Egypt and Syria (305-313) Saint Paphnutius had his right eye removed and his left hamstring cut in an effort to make him recount his Christian views. Even under this terrible torture, he refused to yield and continued to profess his beliefs. Eventually, Maximinus condemned him to manual labor in an Egyptian mine. His left leg was now effectively useless.
Once the persecution ended, he returned to his church and began caring for the Christians that had also been tortured and attacked. He firmly stood against the Arian heresy as it tried to spread throughout the region. When Constantine the Great allowed Christianity, tradition holds that he frequently met with the bishop, kissing the wound of his left eye as a show of respect.
He was called upon to be present the First Ecumenical Council. He was a strong proponent of agreeing with the Nicene Creed. The council also debated clerical celibacy. He took the position that married priests should be allowed to be married and only those who were unmarried at the time of their ordination should remain celibate. His own strict observance of chastity gave his arguments weight at the council.
Saint Paphnutius traveled as far as Jerusalem to combat Arianism, helping the Bishop Maximus of Jerusalem to confess and return to the church away from Arianism. The last record we have of Sain Paphnutius was at the First Synod of Tyre in 335 AD where he attended with 47 other bishops and Saint Athanasius.