Some XVI Century Documents on the Position of the Church about Slavery and Human Trade
Pope Paul III, Encyclical Sublimus Dei, 1537 (on slavery and exploitation of American Aborigines)
[...] "The enemy of the human race, who opposes all good deeds in order to bring men to destruction, beholding and envying this, invented a means never before heard of, by which he might hinder the preaching of God's word of Salvation to the people: he inspired his satellites who, to please him, have not hesitated to publish abroad that the Indians of the West and the South, and other people of whom We have recent knowledge should be treated as dumb brutes created for our service, pretending that they are incapable of receiving the Catholic Faith.
We, who, though unworthy, exercise on earth the power of our Lord and seek with all our might to bring those sheep of His flock who are outside into the fold committed to our charge, consider, however, that the Indians are truly men and that they are not only capable of understanding the Catholic Faith but, according to our information, they desire exceedingly to receive it. Desiring to provide ample remedy for these evils, We define and declare by these Our letters, or by any translation thereof signed by any notary public and sealed with the seal of any ecclesiastical dignitary, to which the same credit shall be given as to the originals, that, notwithstanding whatever may have been or may be said to the contrary, the said Indians and all other people who may later be discovered by Christians, are by no means to be deprived of their liberty or the possession of their property, even though they be outside the faith of Jesus Christ; and that they may and should, freely and legitimately, enjoy their liberty and the possession of their property; nor should they be in any way enslaved; should the contrary happen, it shall be null and have no effect".[...]
Bishop Cerqueira's Excommunication edict (taken from: "Japanese Consultation, 1598")
Original in: BRAH, Jesuitas M.21, ff.272-276v Translated by Renzo De Luca,sj)
"Bishop Peter (Martins, Consultation of 1596), after his arrival in Japan, and after he had acquired some knowledge of the country, saw the serious problems resulting from this "servitude" and "servitude system". So, before his departure for India, he prohibited anyone form buying young boys and girls or bringing them out of Japan under penalty of major excommunication (to be incurred automatically and reserved to himself). Persons bought in this way were to be set free and, in addition, a fine of 10 Cruzados was to be paid".
[...]"(Bishop Cerqueira said that) the Fathers had a thorough knowledge of Japan and that there were serious reasons why it was necessary for Bishop (Martins) to publish the aforesaid excommunication. The case of the "servitude system" of Japanese and Koreans was (in the judgment of all the Fathers) very difficult and delicate. From the information he had on this particular subject, he saw that this system was regarded as evil by intelligent persons and believers, not only in China and India but also in Europe; therefore, he felt that in order to accomplish his duty it was necessary for him to renew that excommunication with the same penalties, as he had already told the Fathers he would do after hearing their opinion on the subject."