The medieval Church often succeeded admirably in patriarchal government; but, in the later Middle Ages, two defects rendered her incapable of solving the social problem in any true sense. First, she justified servitude, both in theory and in practice. St Gregory the Great, in a letter often quoted by apologists (lib. VI. ep. 2), wrote in words of lofty generosity concerning two slaves whom he was setting free; but we must remember also that Gregory's papal estates were tilled by thousands of others whom he never attempted to liberate; and in a later letter (lib. IX. ep. 102) we find him actually exerting himself to recover a slave of his own brother, who had escaped with his wife and child and small belongings. St Thomas Aquinas expressly defends servitude as economically expedient (Summa Theol. 1a 2ae, quaest. 94. art. 5, iii.). Servitude was recognised and enforced by Canon Law; e.g. Gratian, Decretum, Causa X. Quaest. ii. c. 3 and Causa XII. Q. ii. c. 39, in which latter case bishops are severely condemned for freeing serfs of the Church. For churchmen, especially monks, were always among the richest holders of serfs; when Theodore of Tarsus came to the Archbishop of Canterbury, he noted that whereas “Greek monks keep no serfs, Roman monks possess them” (Poenitentiale, cap. viii.; Migne, P.L. vol. XCIX. col. 931 C). Nor were churchmen more willing than others to free their bondmen, except on business terms; see, for instance, Fournier's paper in Revue Historique, vol. XXI. (1883). […]