For my entire life where I grew up in the era of the drug culture I've had no problem answering the question, "Is it okay for Christians to smoke marijuana?" It was easy. "The Bible says to obey the authorities (Rom 13:1). They say 'No'. So, our answer is 'No'." But some states have changed that position and others (mine included) are preparing to follow suit. Now I'm going to have to pursue the question further. Is it okay for Christians to smoke marijuana?
First, I need to say that I disagree with those who see a clear answer in 1 Corinthians 6:19. You know, the standard "Christians shouldn't smoke because 'your body is a temple of the Holy Spirit.'" With that kind of perspective, you'd need to avoid living where there is smog, failing to exercise, even eating Twinkies. You would have to see anything unhealthy as sin. The text, however, is about sexual immorality. So I can't give that one as a blanket answer.
So, the first question you'd need to ask should be easy (since I already used it): "Is it legal?" It isn't in the United States. Some states allow it for medical purposes; others for recreational purposes. Federal law still calls it illegal. But it could be argued that "It's legal in my state" ... if it is. If not, you have your answer.
A real question you'd need to ask yourself is "Why?" Why would you want to? What do you hope to accomplish? As believers, we are supposed to love God and love our neighbors, the two rules of Christian living. How will it assist you in doing so? We are commanded to make disciples. How will this make that happen? That is, is this something of value? I can't actually see how it could be. There is, of course, the medical side that could be considered and it might be argued that, from the medical point of view, it might make you better able to serve God. I cannot find any justification from a perspective of God's purposes for us that would include the use of recreational marijuana, but you should ask yourself these kinds of questions.
As it turns out, there are several aspects to marijuana. One is THC, the compound in marijuana that produces psychoactive effects. In nature, plants don't exceed about 30% THC, but we've improved on it and you can get concentrates up to 95%. Clearly the aim of this product is ... psychoactive effects. Another component is cannabidiol (CBD). This stuff isn't psychoactive. In fact, it can counteract the effects of THC. This is the source of medical effects. Some tests suggest that it can reverse alcohol-induced brain damage, decrease social anxiety, treat schizophrenia and even "turn off" the cancer gene found in metastasis. In some forms, it is also a sleep aid. There appears to be a large number of conditions that CBD can affect. So this form would be a different question.
So, what about Scripture? What does it have to say? Obviously, nothing. The effects of marijuana weren't discovered until 1964. Still, God's Word is not completely silent on the subject. We know, for instance, the command
"Do not get drunk with wine, for that is dissipation, but be filled with the Spirit, speaking to one another in psalms and hymns and spiritual songs, singing and making melody with your heart to the Lord; always giving thanks for all things in the name of our Lord Jesus Christ to God, even the Father." (Eph 5:18-20)Paul says we shouldn't be "intoxicated". We would say "under the influence." Paul says it's "dissipation". The word is "profligacy", a shameless waste. Instead, be filled with the Spirit, make melody in your heart to the Lord, give thanks. Lots of things better than "under the influence." But maybe you don't like the connection of "drunk" and "stoned". So how about this?
Now the deeds of the flesh are evident, which are: immorality, impurity, sensuality, idolatry, sorcery, enmities, strife, jealousy, outbursts of anger, disputes, dissensions, factions, envying, drunkenness, carousing, and things like these, of which I forewarn you, just as I have forewarned you, that those who practice such things will not inherit the kingdom of God. (Gal 5:19-21)The deeds of the flesh are focused on self. Part of that selfishness includes "drunkenness". Included in the list is "things like these." Surely you'd have to admit that the use of recreational marijuana is aimed at exactly the kinds of things Paul is warning against -- immorality, impurity, an appeal to the senses, drunkenness or, at least, "thinks like these".
The good news for you is that I don't get to make the rules and you get to examine the Scriptures for yourself and see if this is what was intended. As for me, I cannot seem to correlate "getting high" with anything remotely positive in the life of a Christ-follower. You'll have to decide that for yourself. If it's illegal, the question is pointless. God says not to violate the law. But I'm pretty sure, as America's moral conscience dies, it will be a question for you to examine beyond the legality of it. I hope I've given some useful places to look when you do.