Paul I or Paulus I or Saint Paul the Confessor (died c. 350), sixth bishop of Constantinople, elected first in 337 AD. Paul became involved in the Arian controversy which drew in the Emperor of the West, Constans, and his counterpart in the East, his brother Constantius II. Paul was installed and deposed three times from the See of Constantinople between 337 and 351. He was murdered by strangulation during his third and final exile in Cappadocia. His feast day is on November 6.
He was a native of Thessalonica, a presbyter of Constantinople, and secretary to the aged bishop Alexander of Constantinople, his predecessor in the see. Both the city and its inhabitants suffered much during the Arian controversies. No sooner had Alexander breathed his last than the Arian and Orthodox parties came into open conflict. The Orthodox party prevailed; in 337 Paul was elected and consecrated by bishops who happened to be at Constantinople in the Church of Peace, close to what was afterwards the Hagia Sophia.
The Emperor Constantius II had been away during these events. On his return he was angry at not having been consulted. He summoned a synod of Arian bishops, declared Paul quite unfit for the bishopric, banished him, and transported Eusebius of Nicomedia to Constantinople. This is thought to have been around 339. Paul, seeing himself rendered useless to his flock, while Arianism reigned in the East under the protection of Constantius, took shelter in the West, in the dominions of Constans. He went to Rome where he met Athanasius, who also had been expelled from his see.
Athanasius of Alexandria was then in exile from Alexandria, Marcellus from Ancyra, and Asclepas from Gaza; with them Paul betook himself to Rome and consulted Pope Julius I, who examined their cases severally, found them all staunch to the creed of Nicaea, admitted them to communion, espoused their cause, and wrote strongly to the bishops of the East. Athanasius and Paul recovered their sees; the Eastern bishops replied to Pope Julius altogether declining to act on his advice.