Reply #2: "Sin" is a self referential term

[eridani]

It's like saying that sea water is salty because it has the principle of salinity. The real reason is that traditional morality (of the last 5000 years or so anyway) is firmly rooted in mass murder and genocide. Note the promise to Abraham--as many descendents as there are grains of sand. And where are all those grains of sand supposed to live? The next chapters give all the gory details of successful and partially successful genocide campaigns. (Except that they get to keep the girl children that have not known men for themselves.)

But it won't work unless women are always cranking out babies, especially male ones to be the cannon fodder, and are devalued in every other way. Homosexuality threatens that arrangement. As does female control of reproduction. "Pro-life" means as many kids possible for your family, and mass murder of other peoples' kids to give yours the lebensraum.