Ok... after reading all of the comments on this topic and probably after people have stopped checking this thread for some time now, Ill add my view on marijuana use and Christianity. As of right now in the U.S., weed is illegal and therefore a sin. Marijuana has been illegal for less than 1% of the time it has been in use. It was only due to racism against Mexican/Americans in the early 1900's that eventually led to it being illegal. Looking at this, and the current movement of legislature in favor of marijuana's legalization, its not totally outlandish to think that it will be made legal in the relatively near future.
So now to the discussion on whether or not its wrong in God's eyes if it is a legal thing to do. The Bible says that you should treat your body as a temple, so to condemn marijuana smoking from this point of the Bible it would it would need to be physically harmful to you. So before you go pointing your finger at the pot smoker, think of the last time you ate a cheeseburger from Mcdonald's or BK or wherever you go to eat when your in a hurry. The affects of those greasy, trans fat filled foods have been proven over and over again to cause serious health risks but we don't give it a second thought before feeding your 4-year-old with it. To compare Marijuana and its effects to other drugs like opium or heroin is a mistake. And to the comment earlier comparing it to cigs, weed does not have nicotine in it. Yes, marijuana smoke has tar but it's smoke doesn't leave the lung's cleaning system paralyzed as does cigarettes and it has been proven to not have the same cancer causing effects (It is still unsure if weed can cause cancer or not, but no cancer case has been linked solely to smoking marijuana) . Scientific research has proven that it is not physically harmful or addicting to people and has been approved for medicinal purposes. Please note that just because it doesn't have any physically addicting qualities, im not saying you can't get addicted to it. You can be addicted to anything; eating excessively, gambling, exercising, etc...
As far as it being a gateway drug, what is the evidence for that? The studies that have been done to show that are just polls to see what drug users use what. Try finding a heroin addict that doesn't also drink alcohol. Is alcohol a gateway drug? Its certainly more dangerous then marijuana. Are cigarettes a gateway drug, because outside of every AA or CA or whatever "A" class when it dismisses the majority of the attendees will light up a square? Cigarettes are definitely more dangerous than weed, that isn't even a question in the medical field anymore. Cigarettes contain nicotine, one of the most addictive, harmful drugs known to man, more than heroin, pcp, alcohol, you name it. (Don't believe me? Look it up).
I think the active Christ follower (a.k.a. Christian) wouldn't really have the time to sit around and get stoned or would want to when he/she could be out in the world, helping people and loving God through that. However, I don't see too many things wrong with it and if you can use it to bring more people to God, then I believe that God would support it. When Jesus came to the world, he didn't come to condemn the world but to save it. IF THE LORD OF ALL CREATION DIDN'T CONDEMN PEOPLE WHILE ON EARTH, WHY DO WE THINK WE CAN? When questioned, Jesus said the first and greatest commandment was "Love the Lord your God with all your heart, all your soul, and with all of your strength." And the second is like it, love your neighbor as yourself. ITS ALL ABOUT LOVE. Now I'm not gonna sit here and say I've never smoked weed because I have, and with my experience, it can be easier to love people while stoned (I don't mean that sexually lol).
Is it a sin? Right now, yes. Will it be a sin if weed is legalized? Does it matter? Your first priority as a Christian should be "How do I love God more". Turning to God and relying on Him for everything is exactly what He wants, that I can support with scripture, actually... All of scripture supports this. If you begin to turn to weed or anything else for comfort you begin to fall away from God (sinning). Can you use this God made plant in ways to honor God and help people? Yes I believe you can. The bottom line here is it doesn't matter if you smoke pot. The only thing keeping you from God is yourself. The Bible is filled with messed up, ordinary people who God used to do extraordinary things (Moses, David, Abraham, Paul, basically everyone lol). Turn to the God that loves you and your possibilities are endless. GOD IS LOVE!
there should be some control on who can buy it, when, where and how much...