Ah, yes. But why is/was it wrong?
(HINT: Slavery first became wrong in cultures where the right(s) to private property were not only acknowledged but enforced by the law of the land.)
Wrong because it's hypocritical to the precepts in the Declaration of Independence. If that's what you're trying to get at, I happen to agree. Enslaving another person is abhorrent on some many levels aside from whatever Western christian civilization says.