We have forgotten just how deep a cultural revolution Christianity wrought. In fact, we forget about it precisely because of how deep it was: There are many ideas that we simply take for granted as natural and obvious, when in fact they didn't exist until the arrival of Christianity changed things completely. Take, for instance, the idea of children.
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Various pagan authors describe children as being more like plants than human beings. And this had concrete consequences.
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Children were rudely brought up, and very strong beatings were a normal part of education. In Rome, a child's father had the right to kill him for whatever reason until he came of age.
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One of the most notorious ancient practices that Christianity rebelled against was the frequent practice of expositio, basically the abandonment of unwanted infants.
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Another notorious practice in the ancient world was the sexual exploitation of children.
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But really, Christianity's invention of children — that is, its invention of the cultural idea of children as treasured human beings — was really an outgrowth of its most stupendous and revolutionary idea: the radical equality, and the infinite value, of every single human being as a beloved child of God. If the God who made heaven and Earth chose to reveal himself, not as an emperor, but as a slave punished on the cross, then no one could claim higher dignity than anyone else on the basis of earthly status.