Perhaps you have been inadvertently giving him negative attention? Maybe feeding into him tantrums? Maybe you don't realize you are doing it and perhaps he keeps doing it b/c he sees that he gets attention when he does those things.
In my opinion, it's important that when he is misbehaving, if it's something he's done before and knows not to do, then instantly place him in a 4 minute time out. Don't talk to him when he is in time out - not even to tell him to stay in time out. If he gets out of time out, without saying anything - go back and physically put him in time out as many times as you have to.
When his 4 minutes is over (and it has to be 4 minutes of being still, not 4 minutes of getting up) - Ask him why he had to be put in time out - and don't discuss, just state - "Yes, you were in time out because you did "x" and that is not appropriate (ok)"
While we love our children, they can be trying - but it's important not to let him see you exasperated, or crying, or at your wits end. We all have our moments where we lose our mind - but make sure when he is having a fit/not behaving that he does not see you start crying, and do NOT say things like "Why are you doing this to me?" "don't you love me?" , things like that show him that he can manipulate and "control" your emotions.
Be consistent. For example, if you are at the dinner table and he is throwing food, or playing w/ his utensils or whatever else - then take his plate away and send him away from the table. He will not starve by missing one meal - no matter how much he may complain - DO NOT give him back that plate, then he will see his complaining worked.
If he can't play nice with a toy, then take it away and put it out of sight. Reinforce good behavior as you are taking things away explaining why he is losing the toy.
When you see him behaving properly, no matter what it is, then be sure to compliment his behavior and ask him about his day, or to tell you about his drawing, or whatever else he is doing.
You may feel like a tyrant at first, but he will learn quick that you are serious and that if he wants priveledges, he must behave.
Good luck to you and God Bless!