This is something I’ve thought about for a long time. I consider myself a completely orthodox, practicing Catholic: I believe artificial contraception to be gravely sinful, I go to Mass at least a few times a week and I even try to volunteer as a sidewalk counselor at the local abortuary when I can. I don’t mention these qualities to boast of my own holiness (God knows I’ve got a lot to work to work on), but to indicate that I’m not an ‘anything goes’ cafeteria Catholic. That said, I don’t think the use of marijuana is in and of itself sinful. I don’t use Cannabis, because it is illegal in the United States and it is quite clear in the Catechism that the use of illegal drugs is sinful in that it contributes to “clandestine trafficking and production” of said drugs (CCC#2291). The same verse indicates that the use of “drugs” is immoral unless used for purely therapeutic reasons. To believe that the term ‘drugs’ is all-encompassing is dishonest in that it is clear that the use of tobacco, alcohol (even ‘strong drink,’ see Deut. 14:26.) and caffeine are licit (as long as they aren’t abused, of course). Moreover, the recreational (albeit temperate) use of wine (indisputably a ‘drug’) is quite licit: Neh. 8:10 - Nehemiah commands the faithful to drink sweet wine to celebrate the Lord and His holy day; Psalm 104:15 - the Psalmist writes that “wine gladdens the heart of a man.” God gave us the fruit of the vine to enjoy; Ecclesiastes 9:7 - "drink your wine with a merry heart, for God approves what you do; Wisdom 2:7 - “Let us take our fill of costly wine and perfumes!”; Sir. 31:25-28 - “Wine is like life if drunk in moderation.”; Sir. 40:20 - “Wine gladdens the heart.” (these quotes are from:
scripturecatholic.com/drinking.html). I know from experience (before my ‘reversion’) that the moderate use of marijuana is possible and can be used in the same way as an ice cold brew after a long day’s work. I can’t help but come to the conclusion that should marijuana laws change in the United States, the moderate use of it could be morally acceptable.