Actually, one can look at Genesis (and the downfall of Man) as metaphorical for Man’s changing over from a hunter-gatherer lifestyle to agriculture and herding. And the story seems informed by a certain sense of loss over Man’s simpler days as hunter-gatherers.
So I would say that nostalgia is probably pretty old.
I’m more inclined toward the simple fact that a fresh, properly-made knapped flint blade is considerably sharper than a metal blade could have been easily made at the time, especially on short notice. Sharper blade = cleaner cut that would heal faster and better.
Heh. I think it was more “now go through and circumcise those who aren’t already circumcised”. The first mass circumcision had occurred, I believe, shortly after the Israelites were led out of Egypt. I don’t have the chapter/verse handy, but there’s a scene where Moses goes to fetch his wife and sons so that they can join the rest of the crowd, and his wife gets mad at him because he hadn’t circumcised his own sons. That lack, of course, had been a matter of Moses being away for quite some time, and perhaps “too busy”. Likewise, after 40+ years of wandering in the wilderness, there were probably a lot of people who just hadn’t gotten around to circumcising their sons, along with, perhaps, other people who had joined them along the way during that time. So by the time Joshua was in charge, there were once again a large number of uncircumcised men in the crowd.
Not really on topic about nostalgia, but there are lots of areas in the Hebrew bible where the tools or food are the most simple, basic, with minimal influence of civilization or human technology. The altar for sacrifices was to be made of stones that were not hewn. The Israelites fleeing Egypt ate unleavened bread and roast meat, the most basic foods. Examples abound.