The mediæval Church, inheriting the patristic view, sought not to abolish slavery, but to ameliorate it. Masters were requested, therefore, to provide spouses for their slaves.[357:7] Prayers were offered up constantly for the removal of their hardships.[357:8] They were granted all the Church feast and fast days.[357:9] Among the Christians there were many acts of manumission.[357:10] Constantine and his successors enacted many laws favourable to slaves.[357:11] The barbarian invasion, however, postponed for a thousand years the general emancipation of slaves. The Church itself was a slave-owner and slaves were found on the lands of convents, bishops, and Popes.[358:1] Even one of the Popes, Calistus, had been a slave.[358:2] But at the same time the Church was always an asylum for slaves and sought to protect them from cruel masters. Gregory the Great declared that all slaves held by Jews were free[358:3] and also emancipated heathen slaves upon turning Christian.[358:4] Thus both by precept and example the Church was the one great force paving the way for the gradual abolition of slavery.[358:5] The Church, as the great advocate of peace and order, strove to abolish family feuds, blood-revenge, and private wars by substituting legal action and legal penalty against the author of crime.[358:6] The synod of Toledo in 693 forbade duels and private feuds.[358:7] The synod of Charroux in 989 and the Bishop of Puy in 990 proclaimed the "Peace of God."[358:8] The synod of Poitiers in 1004, in proclaiming the "Peace of God," decided that law should replace force in determining questions of justice. The synod of Limoges in 1031 issued an interdict against bloody feuds. The Church everywhere sought to have disputes settled by fines rather than fighting, by arbitration rather than litigation, by witnesses rather than by duels. The efforts of the Church in this era of lawlessness, of wanton bloodshed, and of insecurity of property, to maintain peace and to secure justice form one of the most glorious chapters in her remarkable career. The Popes wrote letters and published encyclicals to recommend vows and habits of concord to all Christian nations. Great councils were called to spread abroad ideas of amity and brotherly love. The clergy preached it and enthusiastic monks went from village to village to proclaim it in the name of the "Prince of Peace." A veritable crusade of peace swept over Europe, and denounced war as anti-Christian. Brotherhoods of the Peace of God were formed to curb the militant feudal barons and to protect commerce, agriculture, women, children, travellers, strangers, and holy clerks. When the whole ecclesiastical machinery of the Church, with its power to withhold salvation gained through the holy sacraments and with its mighty weapons of excommunication and interdict, was wielded in behalf of peace, it was a force that could not easily be resisted.[359:1] To the Church,