It is hard to conceive of a greater responsibility than that of a mediæval Inquisitor. The life or death of the heretic was practically at his disposal. The Church, therefore, required him to possess in a pre-eminent degree the qualities of an impartial judge. Bernard Gui, the most experienced Inquisitor of his time (1308-1323), thus paints for us the portrait of the ideal Inquisitor: "He should be diligent and fervent in his zeal for religious truth, for the salvation of souls, and for the destruction of heresy. He should always be calm in times of trial and difficulty, and never give way to outbursts of anger or temper. He should be a brave man, ready to face death if necessary, but while never cowardly running from danger, he should never be foolhardy rushing into it. He should be unmoved by the entreaties or the bribes of those who appear before his tribunal; still he must not harden his heart to the point of refusing to delay or mitigate punishment, as circumstances may require from time to time.
"In doubtful cases, he should be very careful not to believe too easily what may appear probable, and yet in reality is false; nor, on the other hand, should he stubbornly refuse to believe what may appear improbable, and yet is frequently true. He should zealously discuss and examine every case, so as to be sure to make a just decision…. Let the love of truth and mercy, the special qualities of every good judge, shine in his countenance, and let his sentences never be prompted by avarice or cruelty."[1]
[1] Practica Inquisitionis, pars 6a, ed. Douais, 1886, pp. 231-233.
This portrait corresponds to the idea that Gregory IX had of the true Inquisitor. In the instructions which he gave to the terrible Conrad of Marburg, October 21, 1223, he took good care to warn him to be prudent as well as zealous: "Punish if you will," he said, "the wicked and perverse, but see that no innocent person suffers a your hands:" ut puniatur sic temeritas perversorum, quod innocentiæ puritas non lædatur. Gregory IX cannot be accused of injustice, but he will ever be remembered as the Pope who established the Inquisition as a permanent tribunal, and did his utmost to enforce everywhere the death penalty for heresy.
This Pope was, in certain respects, a very slave to the letter of the law. The protests of St. Augustine and many other early Fathers did not affect him in the least. In the beginning, while he was legate, he merely insisted upon the enforcement of the penal code of Innocent III, which did not decree any punishment severer than banishment, but he soon began to regard heresy as a crime similar to treason, and therefore subject to the same penalty, death. Certain ecclesiastics of his court with extremely logical minds, and rulers like Pedro II of Aragon and Frederic II, had reached the same conclusion, even before he did. Finally, in the fourth year of his pontificate, and undoubtedly after mature deliberation, he decided to compel the princes and the podestà to enforce the law condemning heretics to the stake.
He did his utmost to bring this about. He did not forget, however, that the Church could not concern herself in sentences of death. In fact, his law of 1231 decrees that: "Heretics condemned by the Church are to be handed over to the secular courts to receive due punishment (animadversio debita)."[1] The emperor Frederic II had the same notion of the distinction between the two powers. His law of 1224 points out carefully that heretics convicted by an ecclesiastical trial are to be burned in the name of the civil authority: auctoritate nostra ignis judicio concremandus.[2] The imperial law of 1232 likewise declares that heretics condemned by the Church are to be brought before a secular tribunal to receive the punishment they deserve.[3] This explains why Gregory IX did not believe that in handing over heretics to the secular arm he participated directly or indirectly in a death sentence.[4] The tribunals of the Inquisition which he established in no way modified this concept of ecclesiastical justice. The Papacy, the guardian of orthodoxy for the universal Church, simply found that the Dominicans and the Franciscans were more docile instruments than the episcopate for the suppresion of heresy. But whether the Inquisition was under the direction of the bishops or the monks, it could have been conducted on the same lines.
[1] Decretales, cap. xv, De Hæreticis, lib. v, tit. vii.
[2] Mon. Germ., Leges, sect. iv, vol. ii, p. 126.
[3] Ibid., p. 196.
[4] Lea writes (op. cit., vol. i, p. 536, note): "Gregory IX had no scruple in asserting the duty of the Church to shed the blood of heretics." In a brief of 1234 to the Archbishop of Sens, he says: Nec enim decuit Apostolicam Sedem, in oculis suis cum Madianita coeunte Judæo, manum suam a sanguine prohibere, ne si secus ageret non custodire populum Israel … videretur. Ripoll, i, 66. This is certainly a serious charge, but the citation he gives implies something altogether different. Lea has been deceived himself, and in turn has misled his readers, by a comparison which he mistook for a doctrinal document. The context, we think, clearly shows that the Pope was making a comparison between the Holy See and the Jewish leader Phinees, who had slain an Israelite and a harlot of Madian, in the very act of their crime (Num. xxv. 6, 7). That does not imply that the Church use the same weapons. Even if the comparison is not a very happy one, still we must not exaggerate its import. The Pope's letter did not even mention the execution of heretics. Ripoll, Bullarium ord. FF. Prædicatorum, vol. 1, p. 66.