Look up Jesus and the Centurion.
Pope Eugene IV in 1435 wrote to Bishop Ferdinand of Lanzarote in his Bull, Sicut Dudum:
...They have deprived the natives of their property or turned it to their own use, and have subjected some of the inhabitants of said islands to perpetual slavery, sold them to other persons and committed other various illicit and evil deeds against them... We order and command all and each of the faithful of each sex that, within the space of fifteen days of the publication of these letters in the place where they live, that they restore to their earlier liberty all and each person of either sex who were once residents of said Canary Islands...who have been made subject to slavery. These people are to be totally and perpetually free and are to be let go without the exaction or reception of any money...
and if this Bull was not followed the Spanish and Flemish would get excommunicated. You do realise the extent of that punishment, right?
eternal damnation.
Pope Paul III in 1537 issued a Bull against slavery, entitled Sublimis Deus, to the universal Church. He wrote:
...The exalted God loved the human race so much that He created man in such a condition that he was not only a sharer in good as are other creatures, but also that he would be able to reach and see face to face the inaccessible and invisible Supreme Good... Seeing this and envying it, the enemy of the human race, who always opposes all good men so that the race may perish, has thought up a way, unheard of before now, by which he might impede the saving word of God from being preached to the nations. He (Satan) has stirred up some of his allies who, desiring to satisfy their own avarice, are presuming to assert far and wide that the Indians...be reduced to our service like brute animals, under the pretext that they are lacking the Catholic faith. And they reduce them to slavery, treating them with afflictions they would scarcely use with brute animals... by our Apostolic Authority decree and declare by these present letters that the same Indians and all other peoples - even though they are outside the faith - ...should not be deprived of their liberty... Rather they are to be able to use and enjoy this liberty and this ownership of property freely and licitly, and are not to be reduced to slavery...
but then again, Jesus was born in a culture where slavery was normal.
but there is a difference in forms of slavery.
you had "voluntarily" (mostly to pay off debts and release was on the jubliee year) and involuntarily slavery.
anyway something interesting I found:
Slavery and the first Christians
But did the early Church endorse slavery? Certainly, the early Christians more or less tolerated the slavery of their day, as seen from the New Testament itself and the fact that after Christianity became the religion of the Roman Empire, slavery was not immediately outlawed. Even so, this doesn’t mean Christianity was compatible with Roman slavery or that the early Church did not contribute to its demise. In that regard, there are a number of important points to be kept in mind.
First, while Paul told slaves to obey their masters, he made no general defense of slavery, anymore than he made a general defense of the pagan government of Rome, which Christians were also instructed to obey despite its injustices (cf. Rom. 13:1-7). He seems simply to have regarded slavery as an intractable part of the social order, an order that he may well have thought would pass away shortly (1 Cor. 7:29-31).
Second, Paul told masters to treat their slaves justly and kindly (Eph 6:9; Col 4:1), implying that slaves are not mere property for masters to do with as they please.
Third, Paul implied that the brotherhood shared by Christians is ultimately incompatible with chattel slavery. In the case of the runaway slave Onesimus, Paul wrote to Philemon, the slave’s master, instructing him to receive Onesimus back “no longer as a slave but more than a slave, a brother” (Philem. 6). With respect to salvation in Christ,
Paul insisted that “there is neither slave nor free . . . you are all one in Christ Jesus” (Gal. 3:27-28).
Fourth, the Christian principles of charity (“love your neighbor as yourself) and the Golden Rule (“Do unto others as you would have them to do unto you”
espoused by the New Testament writers are ultimately incompatible with chattel slavery, even if, because of its deeply established role as a social institution, this point was not clearly understood by all at the time.
Fifth, while the Christian Empire didn’t immediately outlaw slavery, some Church fathers (such as Gregory of Nyssa and John Chrysostom) strongly denounced it. But then, the state has often failed to enact a just social order in accordance with Church teachings.
Sixth, some early Christians liberated their slaves, while some churches redeemed slaves using the congregation’s common means. Other Christians even sacrificially sold themselves into slavery to emancipate others.
Seventh, even where slavery was not altogether repudiated, slaves and free men had equal access to the sacraments, and many clerics were from slave backgrounds, including two popes (Pius I and Callistus). This implies a fundamental equality incompatible with slavery.
Eighth, the Church ameliorated the harsher aspects of slavery in the Empire, even trying to protect slaves by law, until slavery all but disappeared in the West. It was, of course, to re-emerge during the Renaissance, as Europeans encountered Muslim slave traders and the indigenous peoples of the Americas
.
