From Jordan B. Peterson, 12 Rules for Life: An Antidote to Chaos (Toronto: Random House Canada, 2018), 186-187.
Christianity achieved the well-nigh impossible. The Christian doctrine elevated the individual soul, placing slave and master and commoner and nobleman alike on the same metaphysical footing, rendering them equal before God and the law. Christianity insisted that even the king was only one among many. For something so contrary to all apparent evidence to find its footing, the idea that worldly power and prominence were indicators of God’s particular favor had to be radically de-emphasized. This was partly accomplished throught the strange Christian insistence that salvation could not be obtained through effort or worth — through “works.” Whatever its limitations, the development of such doctrine prevented king, aristocrat and wealthy merchant alike from lording it morally over the commoner. In consequence, the metaphysical conception of the implicit transcendent worth of each and every soul established itself against impossible odds as the fundamental presupposition of Western law and society. That was not the case in the world of the past, and is not the case yet in most places of the world of the present. It is in fact nothing short of a miracle (and we should keep this fact firmly before our eyes) that the hierarchical slave-based societies of our ancestors reorganized themselves, under the sway of an ethical/religious revelation, such that the ownership and absolute domination of another person came to be viewed as wrong.