If you don't believe in a literal interpretation of Genesis, then how do you rationalize your historical understanding of their son Cain?
As I said earlier,
I do not espouse a literal interpretation of Genesis. But
even if you did hold to strict Biblical literalism, the argument that
if the event occurred, God must have
wanted it to occur - simply makes no sense.
Genesis records many human actions that are clearly not good.
The flaw, here, is easily demonstrable.
If you can say...
"In Genesis, people committed incest,
therefore God is pro-incest,"
then you could just as easily say...
"In Genesis, Noah got drunk,
therefore God is pro-drunkenness."
or...
"In the Gospels, Judas betrayed Christ,
therefore God is pro-Christ-betrayal."
It just doesn't work.
Point being -
whether or not you hold to a literal interpretation of Scripture, you cannot argue that because incest occurred, it is therefore morally permissible.
Are we ok on that? Can we get back to the two OP questions?
Anyway. We can leave it at that if you want.
Oh, alright.
We both agree that incest is present in the Bible, that God allowed it, that immediate-family incest is immoral and illegal, that there are mitigating cultural factors in relations outside immediate family (cousins, etc., none of which is all that common as far as I know).
Right.
I am still interested in your reasoning, here.
Why is incest immoral?
Why should incestuous marriage not be legalized?