It must not be forgotten that we are dealing purely with theory.  In fact the Church did an inestimable amount of good to the servile classes, and, at the time that Aquinas wrote, thanks to the operation of Christianity in this respect, the old Roman slavery had completely disappeared.  The nearest approach to ancient slavery in the Middle Ages was serfdom, which was simply a step in the transition from slavery to free labour.[1] Moreover, the rights of the master over the slave were strictly confined to the disposal of his services; the ancient absolute right over his body had completely disappeared.  ’In those things,’ says St. Thomas, ’which appertain to the disposition of human acts and things, the subject is bound to obey his superior according to the reason of the superiority; thus a soldier must obey his officer in those things which appertain to war; a slave his master in those things which appertain to the carrying out of his servile works.’[2] ‘Slavery does not abolish the natural equality of man,’ says a writer who is quoted by the Catholic Encyclopaedia as correctly stating the Catholic doctrine on the subject prior to the eighteenth century, ’hence by slavery one man is understood to become subject to the dominion of another to the extent that the master has a perfect right to the services which one man may justly perform for another.’[3] Biel, who lays down the justice of slavery so unambiguously, is no less clear in his statement of the limitations of the right.  ’The body of the slave is not simply in the power of the master as the body of an ox is; nor can the master kill or mutilate the slave, nor abuse him contrary to the law of God.  The temporal gains derived from the labour of the slave belong to the master; but the master is bound to provide the slave with the necessaries of life.’[4] Rambaud very properly points out that the reason that the scholastic writers did not fulminate in as strong and as frequent language against the tyranny of masters, was not that they felt less strongly on the subject, but that the abuses of the ancient slave system had almost entirely disappeared under the influence of Christian teaching.[5]

[Footnote 1:  Wallon, op. cit., vol. iii. p. 93; Brants, op. cit., p. 87.]

[Footnote 2:  II. ii. 104, 5.]

[Footnote 3:  Gerdil., Comp.  Inst.  Civ.  I., vii.]

[Footnote 4:  Biel, op. cit., iv. xv. 5.]

[Footnote 5:  Op. cit., p. 83.]

On the other hand, it must not be imagined, as has sometimes been suggested, that the slavery defended by Aquinas was not real slavery, but rather the ordinary modern relation between employer and employed.  Such an interpretation is definitely disproved by a passage of the article on justice where Aquinas says that ’inducing a slave to leave his master is properly an injury against the person ... and, since the slave is his master’s chattel, it is referred to theft.’[1]