Mentally prepare for an exchange with the student. Give yourself 30 seconds to cool down before addressing him. Take three deep breaths, filling your lungs with air and then exhaling slowly. This will help you maintain a sense of calm.
Ask the student to leave the class so that you can talk to him one-on-one. Do not confront him in front of the other students since this may give him an opportunity to undermine your authority in front of the class.
Talk to the student about the situation that led to the confrontation. Ask him whether he had an experience prior to coming to class which precipitated the behavior in question. If he concedes that he was simply in a tense mood due to external circumstances, give him five minutes to calm down before returning to class.
Give the student the opportunity to speak about the issue at hand. If he has a long story to tell, listen to it in its entirety; only interrupt him to ask questions. Remember that it's important not to interject whenever he says something that you may find objectionable.
Inform the student of your final decision. After hearing his side of the story and asking questions, either apologize for coming to a conclusion too quickly or tell him firmly that you have decided to maintain the stance that he may have disagreed with in the first place. If he continues to argue with you after you have done this, tell him he cannot re-enter the classroom unless he stops.