course lust is a sin...to some extent.
masturbating isnt necessarily lust.
its sexual exploration.
to epistole: you go off on a tangent of lust and such. Well it depends on who you masterbate too. sometimes you dont masturbate to an image of anyone! (like anime).
but a single guy who isnt commited to matrimony (yet or never would) never does commit the sin of adultry cuz technically hes not married yet.
well
you go on and on about lusting.
many people like other people, like in high school. you see these lists of top 10 hottest hotties, are they lusting?
you are just taking this way too deep than it is.
why do YOU have a problem with others masturbating n e way? it seems a little odd....