Sin is doing something outside of the Biblical LAW. Yes, abortion is the taking of a life and is SIN. The Bible describes Marriage and deciding marriage is something else is SIN. I also believe that drinking alcohol, which is a corruption of grape juice, is SIN....
WADR, you can regard it as sin, but that view is not Biblical. Drunkenness is certainly sin, but not drinking alcohol per se. (This kind of stuff gets too close to Islam. Did Jesus turn water into corrupted grape juice at the wedding in Cana, then?)
I also believe that drinking alcohol, which is a corruption of grape juice, is SIN
The rather obvious question: So, did Jesus sin when he converted water into wine?
Use some discernment.