In fact, the execution of heretics which occurred during the eleventh and twelfth centuries were due to the impulse of the moment. As an historian has remarked: "These heretics were not punished for a crime against the law; for there was no legal crime of heresy and no penalty prescribed. But the men of the day adopted what they considered a measure of public safety, to put an end to a public danger."[1] [1] Julien Havet, _L'hérésie et le bras seculier au moyen âge_, in his OEuvres, vol. ii, p. 134. Far from encouraging the people and the princes in their attitude, the Church through her bishops, teachers, and councils continued to declare that she had a horror of bloodshed: _A domo sacerdotis sanguinis questio remota sit_, writes Geroch of Reichersberg.[1] Peter Cantor also insists on the same idea. "Even if they are proved guilty by the judgment of God," he writes, "the Cathari ought not to be sentenced to death, because this sentence is in a way ecclesiastical, being made always in the presence of a priest. If then they are executed, the priest is responsible for their death, for he by whose authority a thing is done is responsible therefor."[2] [1] _De investigatione Antichristi_, lib. i, cap. xlii, 1oc. cit., pp. 88, 89. [2] _Verbum abbreviatum_, cap. lxxviii, Migne, P.L., vol. ccv, col. 231. Was excommunication to be the only penalty for heresy? Yes, answered Wazo, Leo IX, and the Council of Reims in the middle of the eleventh century. But later on the growth of the evil induced the churchmen of the time to call upon the aid of the civil power. They thought that the Church's excommunication required a temporal sanction. They therefore called upon the princes to banish heretics from their dominions, and to imprison those who refused to be converted. Such was the theory of the twelfth century. We must not forget, however, that the penalty of imprisonment, which was at first a monastic punishment, had two objects in view: to prevent heretics from spreading their doctrines, and to give them an opportunity of atoning for their sins. In the minds of the ecclesiastical judges, it possessed a penitential, almost a sacramental character. In a period when all Europe was Catholic, it could well supplant exile and banishment, which were the severest civil penalties after the death penalty. CHAPTER IV FOURTH PERIOD FROM GRATIAN TO INNOCENT III THE INFLUENCE OF THE CANON LAW, AND THE REVIVAL OF THE ROMAN LAW THE development of the Canon law and the revival of the Roman law could not but exercise a great influence upon the minds of princes and churchmen with regard to the suppression of heresy; in fact, they were the cause of a legislation of persecution, which was adopted by every country of Christendom.