questioning patrick

Adam and Eve had Cain and Abel, that's how.

And Seth and other sons and daughters.

incest

Aah

It technically wasn’t incest yet since they would have had virtually perfect genetic code, and the fact that sibling marriage wasn’t outlawed until Israel was formed as a nation. (see abraham and Sarah)

But murder also wasn't outlawed until Israel was formed as a nation, so that would mean Cain killing Abel wasn't wrong

God told him not to, God clearly described to Cain that his inclination of Murder towards his brother was "sin" when he said "sin is crouching at your door." Also, Abraham married his half-sister, and there was on problem with that. Some of the laws in the Bible are "natural laws" like, let your field rest so that you don't destroy the environment, and "moral laws" like, don't murder people. Don't marry your siblings falls into "natural laws". There are some rules that are added later for the benefit of human society, such as laws on close-kin marriages. As we can see with the Hapsburg dynasty, there was a very real biological reason for this. I have a suspicion that is also why plural marriage is outlawed in the New Testament, because it reduces the genetic diversity of a society. Also, it used to be quite common for even first cousins to marry each other, but that has changed too. As humans acquire more and more genetic defects, close-kin relationships become more and more dangerous to the potential offspring that might arise, meaning the number of acceptable spouses one could take must move further and further from your own family in order to keep healthy genetics.

"God told him not to"

When?

"God clearly described to Cain that his inclination of Murder towards his brother was "sin" when he said "sin is crouching at your door." "

He didn't prohibit murder until later on in the Bible

"Some of the laws in the Bible are "natural laws" like, let your field rest so that you don't destroy the environment, and "moral laws" like, don't murder people. Don't marry your siblings falls into "natural laws"."

If they're natural laws, we can figure them out on our own so we don't need god to tell them to us

"There are some rules that are added later for the benefit of human society"

How do slavery and genocide and child marriage and honor killings benefit society? How does it benefit society to kill people for blasphemy or worshipping other gods? How does it benefit society to kill people for picking up sticks on a certain day of the week? Should we follow those laws today?

"I have a suspicion that is also why plural marriage is outlawed in the New Testament, because it reduces the genetic diversity of a society"

Like reducing the entire human population to eight people, half of whom were related?

"Also, it used to be quite common for even first cousins to marry each other, but that has changed too"

That is still pretty common in some places (like the Bible Belt)

Yes, natural laws don't need to be commanded by God, which is why many natural laws arise in many different cultures.

In terms of benefitting society for killing people who worshipped other god, the answer is simple: Those pagans practiced horrible human sacrifices and terrible abuses against women and children, such as forced prostitution of women and children, torture, cannibalism, and slow and painful execution as sacrifices to "the gods". That is why those societies needed to be eradicated: they committed some of the most heinous crimes known to man as a general, societally accepted rule.

Slavery in the Biblical sense was more or less a "debtors prison." instead of putting people who couldn't pay their debts in jail, they put them to work. It is in fact, from a purely economic standpoint, very beneficial. People who are a drag on society are instead employed to add to the society instead of taking away from it.

Cousin marriage is not "wrong" but it is not beneficial to humans. Also, if you read the flood account, the lifespans of Noah's grandchildren and great-grandchildren drops significantly likely due to the fact that Noah's grandchildren married each other. Cousin marriage wasn't wrong, its just dumb in this day and age. especially when people have access to a much more varied gene pool when looking for a spouse.

Just because God didn't outright say "don't kill your brother" doesn't mean God wasn't saying it was ok. God was specifically saying it was wrong, and to not do it. Cain did so anyways because God gives us the choice. Your response here does not make much sense.

Every response you have made to me has followed the formula of "thing I said" You say: nO iTs nOt, then you state an unrelated fact as though it proves your point.