Let me preface this by saying my experience with religion is very different than your average person. My father is Pakistani, and since the 80s he hasn't identified as a Muslim. My mother is Irish American, and has been an atheist all her life. I was raised an atheist, but my parents maintained several friendships with their religious Muslim friends.
My memory of visiting these friends as a child is that they would go to pray several times a day, and I'd sit alone for a bit, waiting for them to return. They never questioned why I didn't pray, or why I didn't eat only Kosher/Halal meat. I didn't eat pork, so we had that in common, but by the time I reached adulthood we drifted apart as I started drinking regularly.
Since then their lives have gone in their own direction, and mine has gone in mine. When I've seen them since we've been very cordial, but haven't had a ton in common. That is, until I realized that I didn't have much in common with any of my friends. I realized that most of my friends that I saw regularly were either “stoner buddies” or “drinking buddies”.
At this time I was going through quite a bit getting diagnosed with epilepsy. It was taking me forever to get used to my prescription meds, and I soon realized that I was going to have to quit drinking if I wanted to be seizure free. My drinking friends were understanding of my situation, but they still pressured me to drink with them. I often capitulated, only to regret it when I'd wake up in the middle of the night, seizing in a puddle of my own sweat.
I continued to hang with my stoner friends, but since being diagnosed, I had made the choice to try and use cannabis holistically rather than holistically as well as recreationally (I found that using recreationally messed with my tolerance, and increased my consumption without any more seizure relief than I would get from using less herb). My stoner friends continued to hang with me, but often gave me shit for having changed. When I got my MMj certification many of these friends expected me to help them get herb, and when I refused they tried to claim MMJ was just an excuse for me to get high.
Now you're probably wondering what this has to do with religion. Well realizing that I didn't share many common values with my friends put me in quite a depression. I still saw my friends, but seeing them wasn't the same as it used to be, as I realized that our relationship was a bit superficial. This got me thinking about all the friends I had had throughout my life, and my connection to them. I started thinking about how my actions have affected those around me, and realized that my friends weren't the only one's to blame for the state of our relationship. I was just as much guilty of egging my friends on to drink or do drugs, and I was just the first one to get tired of it all. Realizing this made me realize the importance of being accountable for one's actions, which is what inspired me to become more spiritual and introspective.
When I was an atheist my introspection was always circular. I'd often mediate alone, trying to find meaning behind my stagnant existence. The conclusions I'd come too were often depressing. Often I'd justify my negative thoughts or emotions with the conclusion that we all die anyways, so nothing really matters.
It wasn't until my grandmother was diagnosed with lung cancer that I realized the positive impact religion can have on a person. My grandmother was always a devout Muslim, and all my life she visited us, despite my family's lack of religion. She was the only one who kept in contact with my alcoholic aunt, who even my parents, (who are not Muslim, and enjoy drinking alcohol), had dropped contact with. Before my grandmother's diagnosis, my aunt quit drinking all together, and last Summer I saw her for the first time in over ten years. Soon after that came my grandmother's diagnosis. Realizing my grandmother (who we had always sidelined for being too religious) didn't have much time left on this earth, I decided to give her her dying wish. I decided that next time I talked to her I'd tell her I was converting to Islam. I wasn't sure how much I'd actually embrace the religion, but I was sure that hearing those words would bring my grandmother joy in her dying time.
As for cannabis being accepted by Islam, what is taught in most main stream schools of Islam, is that anything that is intoxicating is Haram, and anything that causes harm to the body is Haram. Alcohol is explicitly forbidden, but other drugs are not specified. I have heard the first reason be used against recreation cannabis use, and the second reason be used against smoking of any kind. Neither of these reasons I have heard being used against vaporizing for medical reasons (as vaporizing is not bad for the body, and most Mmj users only vape to the point of relief, not intoxication).
Even when considering recreational cannabis use, there is debate, as smoking tobacco and cannabis is very prevalent (and has a long history) in the Middle East and Central Asia. Go to any Mosque and as long as it's not Ramadan you'll likely see a bunch of bearded guys outside smoking ciggs. The strict anti smoking laws are only instituted by ultra conservative Islamic institutions (like ISIS in Iraq or some of the Muslim countires in South East Asia). Even the UAE, which has very strict laws about everything, tolerates cigarette dokha and hookah smoking.
This came out longer than I wanted, but the main point I'd like to make is that Islam, like every other religion, has hardliners who will try and adhere to the strictest rules possible. That doesn't say anything about the religion as a whole, as there are people like me, who are accepted by fellow Muslims, as being Muslim, but who hold our own opinion, based on our own interpretation of ancient scripture.
My Muslim friends know I vape weed. They know I used to drink. They know I have a dog that I love and that I let kiss my face. They know I pray once a day at best, and that I don't fast on Ramadan.
Their interpretation of Islam might tell them that those are not things they should do. But a more fundamental core of Islam is that it is Haram to criticize or point out other people's sins. It's even considered Haram to question if someone is a Muslim (even if they're eating bacon and worshiping Zeus). So whenever I see them. They give me less shit about my personal life than when I see my old drinking buddies who want me to get hammered and chase girls with them, or when I see my stoner buddies who want me to smoke on their bong or blunt.