Cannabis is the devil's weed; today I saw the coolest dude I know turn paranoid and sell his shit

I'm on a trip to the mountains with my boyfriend, and we rented a cabin from a guy who uses drugs. He's a very cool guy, goes to church every morning, and has a very calm manner, and he never asks for payment or brings up the topic of drugs. We liked him, asked him for drugs so we could use them. He said he would bring them. Yesterday he came with three different types of hashish, two different types of weed, and thc syrup. He said the prices and explained how to use each one, took the money and left. Today he came again and was very angry, shouting and paranoid, saying that we had done something with his drugs and that he would call the police if we didn't return them to him, and he took a syringe. I'm scared of him, I don't want him to come back. I thought he was a very reasonable person, but today he was very angry and paranoid, and I'm afraid he'll come back and fight us. He was very calm every time, and today he was angry, nervous, and paranoid.