Possidius was named Bishop of Calama in Numidia (modern day Guelma, Algeria), where he faced opposition from the Donatists (Donatists were followers of Donatus Magnus, a schismatic bishop of Carthage in the mid-fourth century. They believed that the validity of the sacrament depended on the personal virtue of the celebrant. Many North Africans shared this view at the time of Augustine.) Possidius nearly escaped being murdered when Donatist extremists set fire to a house where he had been visiting. Twice he went to Italy to defend the rights of the African Church. He was present at the Councils in Carthage in 403 and 407, and was chosen along with Alypius and Augustine to represent the Catholic Bishops at a famous meeting with the Donatists in Carthage in 411. He also took part in the Councils of Milevi (416) and Carthage (419) which were devoted to challenges caused by the Donatists.
When Calama was conquered by Vandal invaders in 429, Possidius took refuse with Augustine inside the walls of Hippo and was with Augustine when Augustine died in 420. Possidius returned to Calma but in 437 was exiled by King Hunmeric, who suppressed orthodox Christianity and forces Arianism on the territories he conquered. During this time of exile, Possidius completed his famous Life of Augustine. He died in exile around the year 437.
My source of information about St. Possidius was taken from the website maintained by the Augustinian Friars. They also note that the Augustinian Order has celebrated the feasts of Alypius and Possidius since 1671. Pope Clement X confirmed devotion to them on August 19, 1672. The memory of Alypius and Possidius is closely tied, both as monks and bishops, to that of St. Augustine. The Augustinians consider Alypius and Possidius as the two greatest representatives of his monastic legacy. The Augustinians also point out that history does not remember them for this reason alone. They were dedicated Christians, religious, and shepherds of the Church in their own right.
Until next week,
Fr. John