Pelagianism is the belief that original sin did not taint human nature and that mortal will is still capable of choosing good or evil without special Divine aid. Pelagius taught that the human will, as created with its abilities by God, was sufficient to live a sinless life, although he believed that God's grace assisted every good work. Pelagianism has come to be identified with the view, (whether Pelagius agreed or not), that human beings can earn salvation by their own efforts. This theological theory is named after Pelagius (354 - 420 or 440), although he denied, at least at some point in his life, many of the doctrines associated with his name.
Pelagius rejected the Augustinian concept of grace. When Pelagius taught that moral perfection was attainable in this life without the assistance of divine grace through human free will, Augustine contradicted this by saying that perfection was impossible without grace because we are born sinners with a sinful heart and will. The Pelagians charged Augustine on the grounds that the doctrine of original sin amounted to Manichaeism, which taught that the flesh was in itself sinful (and thus denied that Jesus came in the flesh) and this charge would have carried added weight since contemporaries knew that Augustine had himself been a Manichaean layman before converting to mainstream Christianity. Augustine also taught that a person's salvation comes solely through a free gift, the efficacious grace of God, but that this was a gift that one had a free choice to accept or refuse. William P. Farley points out that one distinction between Pelagius and Augustine was that Pelagius had not experienced the same type of struggle with personal sin as had Augustine.
Pelagianism was attacked in 415 at the Council of Diospolis (also known as Lydda; modern Lod) and condemned in 418 at the Council of Carthage. These condemnations were ratified at the Council of Ephesus in 431. The strict moral teachings of the Pelagians were influential in southern Italy and Sicily, where they were openly preached until the death of Julian of Eclanum in 455, and in Britain until the coming of Saint Germanus of Auxerre c 429.
Little or nothing is known about the life of Pelagius, and although he is frequently referred to as a British monk, his origins are no means certain. ("Pelagius" meaning "islander", as in "pelagic") Augustine says that he lived in Rome "for a very long time" and referred to him as "Brito" to distinguish him from a different man called Pelagius of Tarentum. Bede refers to him as "Pelagius Bretto". St. Jerome suggests he was of Scottish descent which at the time would most certainly have meant he was from Ireland, since in the time of Pelagius, "Scots" referred to Irish raiders. Dal Riada, the predecessor to modern Scotland founded by these raiders, was insignificant at the time, if it indeed it existed at all until the three sons of Fergus Mor Mac Earca migrated there from Irish Dalariada in the 6th century. Other sources place his origins in Brittany. He was certainly well known in the Roman province, both for the harsh asceticism of his public life, as well as the power and persuasiveness of his speech. Until his more radical ideas saw daylight, even such pillars of the Church as Augustine referred to him as “saintly.”
The teachings of Pelagius are generally associated with the rejection of original sin and the practice of infant baptism. Although the writings of Pelagius are no longer extant, the eight canons of the Council of Carthage provided corrections to the perceived errors of the early Pelagians. These corrections include:
- Death did not come to Adam from a physical necessity, but through sin.
- New-born children must be baptized on account of original sin.
- Justifying grace not only avails for the forgiveness of past sins, but also gives assistance for the avoidance of future sins.
- The grace of Christ not only discloses the knowledge of God's commandments, but also imparts strength to will and execute them.
- Without God's grace it is not merely more difficult, but absolutely impossible to perform good works.
- Not out of humility, but in truth must we confess ourselves to be sinners.
- The saints refer the petition of the Our Father, "Forgive us our trespasses", not only to others, but also to themselves.
- The saints pronounce the same supplication not from mere humility, but from truthfulness.
Some codices containing a ninth canon : Children dying without baptism do not go to a "middle place" (medius locus), since the non reception of baptism excludes both from the "kingdom of heaven" and from "eternal life". Pelagianism stands in contrast to the official hamartiological system of the Catholic Church that is based on the theology of Saint Augustine of Hippo. Semi-Pelagianism is a modified form of Pelagianism that was also condemned by the Catholic Church at the Second Council of Orange in 529.
Of far-reaching influence upon the further progress of Pelagianism was the friendship which Pelagius developed in Rome with Caelestius, a lawyer of noble (probably Italian) descent. In the capacity of a lay-monk Caelestius endeavoured to convert the practical maxims learnt from Pelagius, into theoretical principles, which he then propagated in Rome. The denial of the transmission of Original Sin seems to have been introduced into Pelagianism by Rufinus the Syrian, who influenced Pelagius' supporter Celestius. Pelagius' views were sometimes misrepresented by his followers and distorted by his opponents. Pelagianism has come to mean – unfairly to its founder - the view that human beings can earn salvation by their own efforts.
Comparison of teaching
Pelagius's views on free will
Pelagius was disturbed by the immorality he encountered in Rome and saw Christians using human fraility as an excuse for their failure to live a Christian life. He taught that the human will, as created with its abilities by God, was sufficient to live a sinless life, although he believed that God's grace assisted every good work. Pelagius, did not believe that all humanity was guilty in Adam's sin, but said that Adam had condemned humankind through bad example. The value of Christ's redemption was, in his opinion, limited mainly to instruction and example. Jerome emerged as one of the chief critics of Pelagianism, because, according to him, sin was an unavoidable part of human nature.
“Whenever I have to speak on the subject of moral instruction and conduct of a holy life, it is my practice first to demonstrate the power and quality of human nature and to show what it is capable of achieving, and then to go on to encourage the mind of my listener to consider the idea of different kinds of virtues, in case it may be of little or no profit to him to be summoned to pursue ends which he has perhaps assumed hitherto to be beyond his reach; for we can never end upon the path of virtue unless we have hope as our guide and compassion."
A follower of Pelagius taught:
"When will a man guilty of any crime or sin accept with a tranquil mind that his wickedness is a product of his own will, not of necessity, and allow what he now strives to attribute to nature to be ascribed to his own free choice? It affords endless comfort to transgressors of the divine law if they are able to believe that their failure to do something is due to inability rather than disinclination, since they understand from their natural wisdom that no one can be judged for failing to do the impossible and that what is justifiable on grounds of impossibility is either a small sin or none at all."
Church Fathers on free will
All of the Church Fathers before Augustine taught that humans have the power of free will and the choice over good and evil.
- Justin Martyr said that "every created being is so constituted as to be capable of vice and virtue. For he can do nothing praiseworthy, if he had not the power of turning either way".
- Theophilus (c.180) said, “If, on the other hand, he would turn to the things of death, disobeying God, he would himself be the cause of death to himself. For God made man free, and with power of himself.”
- Irenaeus said, “But man, being endowed with reason, and in this respect similar to God, having been made free in his will, and with power over himself, is himself his own cause that sometimes he becomes wheat, and sometimes chaff.”
Thomas Bradwardine (c. 1290-1349) wrote De causa Dei contra Pelagium et de virtute causarum ad suos Mertonenses. Johann Pupper, also known as Johannes von Goch (c. 1400-1475), an Augustinian, recommended a return to the text of the Bible as a remedy for Pelagianism.
Later writers, such as Martin Luther (1483-1546), John Calvin (1509-1564), and Cornelius Jansen (1585-1638) reacted in different ways against Pelagianism, and evaluations of Lutheran, Reformed, and Jansenist theologies have often turned on the question of what is or is not Pelagian.
In the book Guardare Cristo: esempi di fede, speranza e carità (Looking at Christ: Examples of faith, hope and charity) Pope Benedict XVI wrote:
"the other face of the same vice is the Pelagianism of the pious. They do not want forgiveness and in general they do not want any real gift from God either. They just want to be in order. They don’t want hope they just want security. Their aim is to gain the right to salvation through a strict practice of religious exercises, through prayers and action. What they lack is humility which is essential in order to love; the humility to receive gifts not just because we deserve it or because of how we act…” 
In a June 2013 talk with the leadership of the Religious Confederation of Latin America and the Caribbean (CLAR), Pope Francis alluded to Pelagian tendencies when he referred to “restorationists”, one group of whom sent him after his election 3,525 rosaries. The pope said he was “bothered” by this need to count prayers and labeled it “pelagianism.” He went on to comment: “these groups return to practices and disciplines I lived – not you, none of you are old – to things that were lived in that moment, but not now, they aren't today....” 
The Church of Jesus Christ of Latter-day Saints
Mormon theologian Sterling M. McMurrin, who ended his life as an atheist, has argued that “[t]he theology of Mormonism is completely Pelagian.” Mormon theology teaches that the Atonement of Jesus Christ has overcome the effects of "original sin" for all mankind. For example, the Book of Mormon, a sacred text for The Church of Jesus Christ of Latter-day Saints, teaches: "[T]he Messiah cometh in the fullness of time, that he might redeem the children of men from the fall. And because they are redeemed from the fall they have become free forever, knowing good and evil; to act for themselves and not to be acted upon, save it be by the punishment of the law at that great and last day, according to the commandments which God has given." It also teaches: "there is no flesh that can dwell in the presence of God, save it be through the merits, and mercy, and grace of the Holy Messiah". Pelagianism is not the official stance of The Church of Jesus Christ of Latter-day Saints.
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