I dont like this. I wouldnt mind him teaching him if only the story gave him an excuse for it. He literally said "i dont have a reason to explain it to you" so why is he teaching him without a reason? There should have been at least a "Hmm, i was from Kunlun so i will teach him for piety for Kunlun." sure the rudeness was pardoned because mc perceived it as "love for kunlun" but would be better if dude have something to give to get his teachings.