If you have ONE error and that SAME error appears on 500 manuscripts, it is viewed as 500 errors and to quote Bruce Metzger, "there has been NO ERROR shown that can cal into question ANY major Christain Doctrine."
Erhman makes that same point in one of his books.
Christ openly and clearly states to love and pray for those that presecute you and are your enemies so ANY faith that advocates violence against them is NOT Christian.
Slavery was not in any way considered persecution in the day. The morals are questionable at best. Paul at the same time speaks of women as prophetesses and in a subsequent letter commands they not be allowed to speak. Jesus also said that he came, not the bring peace but a sword.
Which one of these do we follow? No peace, but pray for your enemies? Women can prophesy but not speak at gatherings? Love those persecuting you but never bother to mention that, oh by the way, owning people as property is persecution?
I think the point is, there are no originals, there are a LOT of reasons to suspect they may have been parts of oral traditions that changed grossly over time and there is no way to know what Jesus "said".