And yet, people keep saying that the bible contains "no contradictions"...
There where these things, way back, called farmer's almanacs. They contained a weird mix of stuff that people swore by. Some of it was contradictory, some of it was commons sense, some of it was even accurate, a lot of it was absurd gibberish, and it contained whole messes of predictions, and rumor, and other nonsense. Some people where **sure** that everything in them was "true*, and they used it for everything. Some, where more selective, but no more rational, or scientific in their interpretations. If one person lost a rash, by smearing some random concoction from the almanac on their skin, everyone in their township heard about it. If it didn't work, they went and tried the next absurd thing suggested.
The OT was written in a time when there where many competing gods, and small nations, or tribes, and the way to "win" was to be the one left standing, after the everyone else was left bleeding on the ground. The NT was written during a time when there was "one" nation, the competition was over which of a dozen faiths you where going to follow, and power came via politics, not war (at least, within Rome, where Christianity and all of the NT appeared). It wasn't necessary to produce masses of extra children. There where already too many of them, too many alternate temptations, too many people that could take you kid and make them a follower of Zeus, or Hera, or some other deity. What mattered was "individuals", how many people could you convince to change sides to the "one true faith", and how effective, if they had kids, they where at making sure those children "stayed" within the same religion (which is a bit harder to manage, if you have dozens of them, and every neighbor has a different religion).
Of course Christianity had to change. And, when all those competing gods went away... then they had to invent Hell (yes, it was invented. The original text mentions three places - Gehenna, a literal physical location, in the real world, where the bodies of the diseased where burned, along with other garbage. We would call this, today, "City Dump". Limbo - a place exactly identical to Hades, where souls merely went to, "wait until their fate is decided". No mention is made of what that fate might be, or when, but its pretty clear that they didn't remember things, know who they where, etc., they just "waited". Tarterus - a prison for, for a lack of a better term, "fallen angels". Heaven... isn't mentioned at all, by comparison. The invention of hell was to make people fear the consequences of not following the, "right version of Christianity", because, without a hell, for the sinners, and a heaven to reward those who did right, the religion that won didn't really have anything to control anyone.
The old ones.. made their gods like people, but more childish. You knew that they where capricious, uncertain, and that you could be rewarded, or punished, for your actions, even if those where sometimes both arbitrary. The new one.. was inscrutable. You never knew, unless the priests told you, what was really wrong, or right, save that kings, and priests, seemed to always be right, and everyone else where either wrong, or hadn't yet been told what they where wrong about (even if they did nothing worse than the kings and the priests where dong). And, what rules did exist.. where a mishmash of things that where a) impossible to avoid, b) go against human nature, often requiring people to be harmed "for their own good", because they did things that cause no harm to others at all, or c) everyone agreed with, more or less, anyway, even the ones breaking them. A rather different set of rules than, "Do not carry beads into Hera's temple on the full moon, less she be offended!", or something similarly clear, tangible, and actually avoidable.