ARNALDO DA BRESCIA. — Born toward the end of the 11th century or at the beginning of the following one in Brescia, he embarked upon an ecclesiastical career, although it is doubtful whether he advanced beyond the minor orders. Of his youth, we know only of his journey to Paris and his stay at the school of Abelardo, of whom he became the most devoted disciple and most ardent defender. After 1119 he returned to his homeland and took part in the struggles taking place in his city against the simoniacal clergy and the temporal authority of the bishop. At that time the consequences of the Investiture Controversy were being felt everywhere and were agitating not only the clergy but especially the lower classes of the cities, which made the moral question an instrument of political rebellion. In Brescia, Bishop Villani favored the antipope Anacleto II, while the consuls supported Innocenzo II; the bishop was replaced by Manfredi, who favored reform but was expelled from the city after a riot. Meanwhile A., having gone much further in his anticlerical stance, which struck at the entire Catholic hierarchical system, was denounced to the Pope for his rebellious conduct and condemned at the Second Lateran Council in 1139. He then returned to France, but there he threw himself into the highly heated disputes that were raging between Abelardo and s. Bernardo, supporting the former; for this reason he was condemned along with him at the Council of Sens and confined to a monastery. Shortly afterward he was able to open a school of moral theology on the mountain of S. Genoveffa, where he resumed his invectives against the worldliness of the clergy, but he had little success. Through the efforts of s. Bernardo, who also sought the help of the king of France, he was expelled and took refuge in Switzerland among the Augustinian canons of Zurich; for some time he also enjoyed the protection of the bishop of Constance, but then s. Bernardo succeeded in exposing him in a bad light, and he had to depart. A., however, had a friend in Cardinal Guido di Costello, then papal legate in Bohemia, and was able to remain peacefully with him; here he met Geroh di Reichersberg, who recommended him to Celestino II. Perhaps in the cardinal’s retinue, A. came to Italy and reached Rome around 1145. The conditions of the city in those years were extremely troubled, since the renecatio senatus had taken place, the restoration of civic autonomy with a distinctly anti-papal character and the ascendancy of popular elements. Some pontiffs who had attempted to oppose the movement had come to a bad end, while others had withdrawn from Rome. At first A. remained uninvolved in the political struggles. After abjuring his errors before Pope Eugenio III at Viterbo,
he was sent by him (apparently) to Rome in the garb of a penitent to undertake an expiatory pilgrimage. Shortly afterward, however, his political passion returned, and he began preaching again, soon gathering a broad following around him. The subject of his discourses was still solely the reform of ecclesiastical morals, the invitation to an ascetic life more in keeping with evangelical ideals. Yet it was inevitable that an understanding should be established between the two movements—the religious movement of A. and the political movement of the Roman senate—given their affinity of programs, the common enemy they had to combat, and the identity of the historical appeals to which both referred. The point of convergence came when A. proclaimed that ecclesiastics should not possess earthly goods and that these were all the property of the laity and therefore of the prince. The clash between the Pontiff and the rebel assumed notably harsh tones: Adriano IV demanded A.’s expulsion, while the senate refused, undertaking to guarantee his safety, and A. swore to defend the republic with his words; in a riot a cardinal was wounded, and the Pope consequently placed the city under interdict. A. had to flee Rome, but at this point a new protagonist entered the scene, whose action proved decisive: Federico Barbarossa, who had recently ascended to the imperial throne and was deeply convinced of his duties as the Church’s armed defender, was delighted to do the Pope a favor, despite the many other grounds for conflict between them. Thus A. was caught by Barbarossa’s partisans and handed over to the city prefect Pietro, who condemned him to death; it is highly probable that he was hanged and then burned. His ashes were thrown into the Tiber so that they would not become objects of veneration for the numerous and fervent followers who still remained in Rome after his death.
It has rightly been observed that A.’s criticisms of the worldly clergy are no more severe or violent than those of a s. Pier Damiani and that, ultimately, he and his great adversary s. Bernardo were combating the same vices in apparently similar forms. Yet the difference between them is truly radical and explains the difference in their success. It is impossible to distinguish how much was personal in A.’s preaching and how much he repeated of concepts and aspirations common to broad strata of the population. He was undoubtedly highly learned, possessed a lively intelligence and was an impassioned speaker; he led an austere life and knew how to instill his sentiments in many people; he wrote nothing, or very little.
THE ARNALDISTS. - This was the name given to those followers of A. who, in the second half of the 12th century, formed a distinct heretical sect in Lombardy; they are nominally condemned in the constitution Ad abolendam of Lucius III and Frederick I Barbarossa (Verona 1184). A. considered the clergy prevaricators and deprived of authority if they did not lead a poor life, without possessions or pomp; his disciples lived by begging. It is not proven that he taught errors regarding the Baptism of children and the Eucharist. The Arnaldists considered evangelical virtues the foundation of the priestly "ordo" and hierarchy; they rejected the Sacraments as ineffective because administered by priests whom they deemed unworthy. They taught that it was obligatory to resist the Church's abusive exercise of judicial and coercive power, and that an austere and poor life gave the laity the right to preach without ecclesiastical approval. They pushed their evangelical pauperism to heterodox doctrinal positions; due to the anti-hierarchical and anti-sacerdotal character of their preaching, they influenced the heretical evolution of the Italian Waldensians (v. VALDESI) and the Humiliati (v. UMILIATI). In the 13th century, they are mentioned in the lists of condemnation of various sects, but they did not endure as a distinct group; their errors became the ferment of other heretical currents.