Editing Pope Leo I (section)

==Papacy==
During Leo's absence in Gaul, [[Pope Sixtus III]] died on 11 August 440, and on 29 September Leo was unanimously elected by the people to succeed him.<ref name=Kirsch1910 /> Soon after assuming the papal throne, Leo learned that in [[Aquileia]], [[Pelagianism|Pelagians]] were received into church communion without formal repudiation of their heresy; he censured this practice and directed that a provincial synod be held where such former Pelagians be required to make an unequivocal [[abjuration]].<ref name="Kirsch1910" />

Leo claimed that [[Manicheism|Manichaeans]], possibly fleeing [[Vandal Kingdom|Vandal Africa]], had come to Rome and secretly organized there.{{sfn|Cohen|2020|p=156}} In late 443, Leo preached a series of sermons condemning the Manichaeans and calling for Romans to denounce suspected heretics to their priests.{{sfn|Cohen|2020|p=139}} Eventually, suspected heretics were brought to court, and likely under torture, they confessed to various crimes.{{sfn|Cohen|2020|p=152}} By early 444, Leo announced to the bishops of Italy that the Manichaeans had been eradicated from Rome.{{sfn|Cohen|2020|p=153}} According to his contemporary [[Prosper of Aquitaine]], Leo exposed the Manichaeans and burned their books.{{sfn|Cohen|2020|p=140}} He was equally firm against the [[Priscillian]]ist sect. Bishop [[Turibius of Astorga]], astonished at the spread of the sect in [[Spain]], had addressed the other Spanish bishops on the subject, sending a copy of his letter to Leo, who took the opportunity to write an extended treatise (21 July 447) against the sect, examining its false teaching in detail and calling for a Spanish general council to investigate whether it had any adherents in the episcopate.<ref name=Crawley>{{Cite web|url=https://www.ewtn.com/catholicism/library/saint-leo-the-great-5614|title=Saint Leo the Great &#124; EWTN|website=EWTN Global Catholic Television Network}}</ref>

From a pastoral perspective, he energized charitable works in a Rome beset by famines, an influx of refugees, and poverty. He further associated the practice of fasting with charity and almsgiving, particularly on the occasion of the ''Quattuor tempora'', (the quarterly [[Ember days]]).<ref name=Butler/> It was during Leo's papacy that the term "Pope", which previously meant any bishop, came to exclusively mean the Bishop of Rome.<ref>Asimov, Isaac (1967) ''The Roman Empire'', Houghton Mifflin: Boston, p. 236</ref>