Far and away the most changes are the result of mistakes pure and simple slips of the pen, accidental omissions, inadvertent additions, misspelled words, blunders of one sort or another.
In terms of the historical record, I should also point out that there is no account in any ancient source whatsoever about King Herod slaughtering children in or around Bethlehem, or anyplace else.
No other author, biblical or otherwise, mentions this event. Is it, like John’s account of Jesus’ death, a detail made up by Matthew in order to make some kind of theological point?
Did he say both things? Could he mean both things? How can both be true at once? Or is it possible that one of the Gospel writers got things switched around?
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