Immorality is based on the perception of the powers that be.
For example. 2000 years ago, a 33 year old man could marry a girl simply because she got on her period.
For example. According to Jewish Law, Eating Pork is a grave sin!!!
Are you saying that morality is constantly changing?
If it is constantly changing, what does that mean about morality itself?
2000 years from now, can a 45 year old man marry his daughter if she is of legal age (i.e 25) and consents to it?
If what what moral yesterday is not longer seen as moral (i.e. teenage marriage) and what was immoral yesterday (i.e. Gay marriage) and now seen as acceptable, does that have anything to do with morality or more with law?
In certain countries, you can marry a very young girl legally - I'd read accounts of Afghanistan where Men above the age of 40 married girls that were in their pre-teens (12-15). It is common there in some instances.
At the same time, if your gay in that society and open about it, you'll end up being stoned to death.
Isn't that more of legal enforcement than law? At the same time, there is underage marriage in American too (see the Fundamentalist Mormons; and persecution of Gays) just that in American there is no force of the Government that enforces such laws but rather the people take things into their own hands.