[1] Can. 4, Labbe, _Concilia_, vol. x, col. 1419.
This canon was applied probably for the first time at Toulouse in 1178. The Bishop began proceedings against several heretics, among them a rich noble named Pierre Mauran, who was summoned before his tribunal, and condemned to make a pilgrimage to the Holy Land. His property was confiscated, although later on when he professed repentance it was restored to him, on condition that he dismantle the towers of his castles, and pay the Count of Toulouse a fine of five hundred pounds of silver.
In this meantime the Cathari increased with alarming rapidity throughout this region. Count Raymond V (1148-1194), wishing to strike terror into them, enacted a law which decreed the confiscation of their property, and death. The people of Toulouse quoted this law later on in a letter to King Pedro of Aragon to justify their sending heretics to the stake, and when the followers of Simon de Montfort arrived in southern France, in 1209, they followed the example of Count Raymond by sending heretics to the stake everywhere they went.
The authenticity of this law has been questioned, on account of its unheard-of severity. But Pedro II, King of Aragon and Count of Barcelona, enacted a law in 1197 which was just as terrible. He banished the Waldenses and all other heretics from his dominions, ordering them to depart before Passion Sunday of the following year (March 23, 1198). After that day, every heretic found in the kingdom or the county was to be sent to the stake, and his property confiscated. It is worthy of remark, that in the king's mind the stake was merely a subsidiary penalty.
In enacting this severe law, Pedro of Aragon declared that he was moved by zeal for the public welfare, and "had simply obeyed the canons of the Holy Roman Church." With the exception of the death penalty by the stake, his reference to the canon law is perfectly accurate. Pope Alexander III, who had been present at the Council of Tours in 1163, renewed, at the Lateran Council in 1179, the decrees already enacted against the heretics of central France. He considered the Cathari, the Brabançons, etc., disturbers of the public welfare, and therefore called upon the princes to protect by force of arms their Christian subjects against the outrages of these heretics. The princes were to imprison all heretics and confiscate their property. The Pope granted indulgences to all who carried on this pious work.