These are... well, kind of disturbing. So my questions are 1) do any of you take these literally? if not, why not? 2) why would there ever be a reason for people to kill and/or eat their children?? and 3) why use the old testament at all? I was always taught that everything in the old testament was archaic and that only the new testament really mattered.
There is a lot of evidence in the OT that the Israelites, in common with just about every other ancient culture, practiced infanticide. If you read through the OT you see lots of references to this, some of them half edited out, some of them left in. At some point a scribe decided that these references did not reflect well on the Israelites, and did a lot of editing, but not everything got edited away.
If you read Kings, you will find that some kings are condemned utterly for abominations. These abominations are spelt out as infanticide. In particular, if you piece them together, the people make their first born children pass through the fire (burn to death) as an offering to the god Molech. Sometimes this happens in a valley, sometimes on a mountain.
It is more than likely, therefore, that the story of Abraham taking Isaac to be sacrificed is one way of persuading the people of that time not to carry out this practice, and to demonstrate to the people that God does not delight in the murder of children. Seen in any other light, the story shows God as a sadist, imho. Seen in that light, it makes perfect sense.
Anyway, read for yourself. You do not need me to tell you what is there, you only need to open your eyes. One king is condemned for practicing abomination in making the children pass through the fire (infanticide), the next is godly, and bans it as a practice, and the next returns to the appalling practices. This happens over and over, and the prophets speak out against it over and over.
It is all there. Ultimately, of course, the Jews move from this to symbolic redemptive sacrifices instead, at first in several places but eventually centred on the Temple at Jerusalem, where a pair of doves or a lamb is offered in the place of the child. Slightly more civilised, and a practise still in place at the time of Our Lord. And of course, all of this underpins the thinking behind the sacrifice of Our Lord himself, as the First Born of his father.
It is a little disturbing to see the echoes of child sacrifice in our own faith, but they are there. And the proof is in the Bible itself.
As for your last question, both the OT and the NT matter. But neither is God. And what matters most of all to a Christian, imo, is not the Bible, but a living relationship with a Living God. One who does not delight in burnt offerings of any kind.
