Born in
Brescia, Arnold became an
Augustinian canon and then
prior of a
monastery in Brescia. He criticized the
Catholic Church's temporal powers that involved it in a land struggle in Brescia against the
Count-Bishop of
Brescia. He called on the Church to renounce its claim and return ownership to the city government so as not to be tainted by possession—renunciation of worldliness being one of his primary teachings. He was condemned at the
Second Lateran Council in 1139 and banished from Italy. According to the chronicler
Otto of Freising, Arnold had studied in
Paris under the tutelage of the reformer and
philosopher Pierre Abélard. He approved of Abélard's proposals for monastic reform. He was also influenced by the French reformer
Henry of Lausanne. He agreed with the several issues they preached, including the issues of
Infant Baptism, and the great wealth of the Roman Church among other things.". The issue came before the
Synod of
Sens in 1141 and both Arnold and Abélard's positions were overruled by
Bernard of Clairvaux. Arnold stood alone against the church's decision after Abélard's capitulation; he returned to Paris, where he continued to teach and preach against Bernard. As a consequence he was then commanded to silence and exiled by
Pope Innocent II. He took refuge first in
Zürich and then probably in
Bavaria. His writings were also
ordered burned as a further measure, though that judgement is the only evidence that he had actually written anything. Arnold continued to preach his radical ideas concerning
apostolic poverty. . Arnold, who is known only from the vituperative condemnation of his foes, was declared to be a
demagogue; his motives were impugned. Having returned to Italy after 1143, in 1145 Arnold made his peace with
Pope Eugene III, who ordered him to submit himself to the mercy of the Church in Rome. When he arrived, he found that
Giordano Pierleoni's followers had asserted the ancient rights of the
commune of Rome, taken control of the city from papal forces, and founded a
republic, the
Commune of Rome. Arnold sided with the people immediately and, after Pierleoni's deposition, soon became the intellectual leader of the Commune, calling for freedoms and democratic rights. Arnold taught that clergy who owned property had no power to perform the
Sacraments. He succeeded in driving Pope Eugene into exile in 1146, for which he was
excommunicated on 15 July 1148. When Pope Eugene returned to the city in 1148, Arnold continued to lead the blossoming republic despite his excommunication. In summing up these events,
Caesar Baronius called Arnold "the father of political heresies", while
Edward Gibbon later expressed his view that "the trumpet of Roman liberty was first sounded by Arnold." After Pope Eugene's death,
Pope Adrian IV swiftly took steps to regain control of
Rome. He allied with
Frederick Barbarossa, who took Rome by force in 1155 after a
Holy Week interdict and forced Arnold again into exile. Arnold was seized by Imperial forces and tried by the
Roman Curia as a rebel. Importantly, he was never accused of
heresy. Faced with the stake, he refused to recant any of his positions. Convicted of rebellion, Arnold was
hanged in June and his body burnt. Because he remained a hero to large sections of the Roman people and the minor clergy, his ashes were cast into the
Tiber, to prevent his burial place becoming venerated as the
shrine of a
martyr. In 1882, after the collapse of Papal temporal powers, the city of Brescia erected a monument to its native son. == Beliefs ==