Teen boy with issues! HELP!?

My son is having some major behavior issues. A lot of people say it is just a phase, but I am not so sure. He is dabbling in tobacco and I have no proof of illicit drugs but have intercepted texts that would indiate such, he also talks of wanting to be wiccan, his grades are ping, but used to be straight A's, he locks himself in his room all the time, he dropped out of sports, he is always disrespectful and hateful, said he was d (but woke up with his "part" in another boys rectum) ??? How's that?? What do I do? He refuses couseling, I have tried and he quits going. He was kicked out of the house for skipping school and not following house rules, he is back now but horrible to live with. He also threatenes to kill me and has an obcession with fire, knives and "dark" things. HELP!