It's no accident that it was Chiristan Europe, and no where else, that pursued the abolition of slavery.
It kind of was an accident, though. It largely happened because the Catholic Church became so obviously corrupt -- selling indulgences for gods' sake! -- that it provoked the Protestant Reformation. That provoked the Counter-Reformation, which led to Europe having religious wars for a couple hundred years, and the horror of those provoked the Enlightenment, which spread the idea that a person's religious opinions were a private matter between him and his God rather than a proper matter to be policed by his rulers, and that instigated the more general idea of limited government and a whole realm of personal liberty, and that discredited authoritarianism in general, and that led to the rise of democracy, first in Britain and America, and later most of the West, and that created a jarring contrast between the liberty of citizens and the imprisonment of slaves. It was that contrast that gave abolitionism a toehold -- in the authoritarian age, slaves being subject to owners didn't look conceptually all that different from commoners being subject to aristocrats and aristocrats being subject to kings.
The same evolution couldn't have gotten started in Islam because Islam had no Pope. It was functionally Protestant from the get-go. So the idea of each individual Muslim having the right to disagree with his Imam and with his blasphemy-persecuting neighbors never got any leverage.
That Christianity had a Pope and Islam didn't sure likes like an accident to me.
Even in the US, those most vocally anti-slavery were deeply Christian. Hello, John Brown.
Well, there was Robert Ingersoll, the famous abolitionist and lecturer on agnosticism. Outnumbered by Christian abolitionists, sure; but then agnostics were outnumbered by Christians.
Moreover, "It is easier for a camel to go through the Eye of the Needle than for a rich man to enter the kingdom of God."
Sure; but remember, that's the kingdom of God, not kingdoms here on earth. The Christian message was always focused on salvation in the next world, not on fixing the problems of this world.
"Slaves, obey your masters in all things. Do not obey just when they are watching you, to gain their favor, but serve them honestly, because you respect the Lord. In all the work you are doing, work the best you can. Work as if you were doing it for the Lord, not for people. Remember that you will receive your reward from the Lord, which he promised to his people. You are serving the Lord Christ." - St. Paul's Epistle to the Colossians, 3:22-24
The whole selling point of Christianity, that Paul espoused, was that everyone could get to heaven through Christ. God loved everyone. Everyone has value.
Exactly. To
Heaven. Not to freedom on Earth.