They aren't. Slavery is compatible (even required) with Islam, but it is quite contrary to Christian principles.
That little phrase — “Masters, give up threatening” — was intended to put all domestic servant arrangements on a voluntary basis. It wasn’t to be a one-sided thing, not in Christendom.
There wasn’t any “except for Southrons” clause in there.
Incidentally it was Arab traders who went and grabbed the slaves, gleaning them from prisoners taken in inter-tribal wars in Africa, by tribes who were all the more happy to pursue the wars when they were rewarded by goodies from Arabs. Talk about wicked and inhuman plans.
And today we’re plagued more and more by Islamists. Maybe we deserved it. Kiss up to the serpent, get bitten.
Yeah. I know dude, believe me I know. Tell CNN and the Democrats, they don’t get that.