@fredsbend Thank you,that is a great answer!

Questions: Before Moses ,did everyone eat pig ( or maybe pig has been seen as unhealty )

@Aigle Noah was to take 2 of every animal, I'm sure you know, but also seven of every clean animal. The Law existed before Moses.

@fredsbend Ok , Im just thinking out loud I am having problems understanding what you can or cant eat.Both sides have a good argument

Do you think pig is unclean because it is unhealty or somthing else?

@Aigle I have no personal problem with eating pig or anything else, except human.

Can't say why it mattered to some ancient peoples.

@fredsbend Better to say the concept existed before Moses. Maybe they had laws, but if so they weren't recorded.

@curiousdannii Or any recordings weren't preserved.

@Aigle I've heard that it was likely because they had parasites Israelites couldn't deal with.

"What you can eat" seems to have developed and changed in the bible.

Then there's interpretation that Jesus made all foods clean, Peter's dream, etc.

@curiousdannii Not all ancient cultures recorded their laws. Often they were simply passed down from elders to the younger members of the culture, and generally inculcated in the young as they grew up, just as happens in every culture. Judgments were commonly rendered by elders at the gate of the city or town—something that is referred to a number of times in the Bible.

@LeeWoofenden After doing some research, pig meat can carry some nasty diseases, especially if eaten undercooked or raw, which the Israelites likely would have done. @Aigis There's also the idolatry angle, pigs were a common sacrifice to pagan gods, particularly Canaanites.

@Piomicron So can meat in general. But a) I don't see any evidence in the Bible that the prohibition on pig meat was for health reasons, and b) I also don't see any evidence in the Bible that the Israelites ate their meat raw. There are frequent references to cooking meat, both in connection with sacrifices and in connection with general rules of eating, in the Old Testament.

I suspect, rather, that the idea that the prohibition on pork was due to the supposed unhealthfulness of eating pork was a much later superimposition on the biblical dietary laws in an attempt to show, based on modern notions of health and disease, that that ol' Moses was a pretty smart cookie when it came to keeping his people healthy.

It's more likely that the dietary laws were based on ancient cultural taboos related to (ritually) "clean" and "unclean" animals. The rules were that for an animal to be "clean," it had to both have a cloven hoof and chew the cud. But there is no particular biological reason to think that the meat of animals that have cloven hooves and chew the cud is more healthful than that of any species that either does not chew the cud or does not have cloven hoofs.

In general, the animals that the Israelites were allowed to eat were the same as the animals that they were allowed to sacrifice. This suggests that health had nothing to do with it, but that it had to do with cultural practices and taboos related to animal sacrifice.