The New Testament Biblical philosophy alludes to the practice of simply shaking the dust off of one’s shoulders and shoes and then moving on. Alternative religious texts should have similar thoughts on being firm when dealing with unreasonable people who choose not to see eye to eye with the other. Speaking of which, there is that controversial age-old teaching of an eye for an eye. Community-oriented courts of law seem to have adopted the alternative practice of not necessarily turning the other cheek but more appropriately perhaps to find ways and means to help that unruly or uncooperative person.
When someone is grossly unreasonable he could have anger management issues. But in being confronted with such a person, it is possible to help that person too. You will be limited in your own powers, and that is quite reasonable. For the time being, the best you could do for that person is to recommend that he take up online anger management courses. And if that angry man decides to cease and desist from taking the proverbial splinters out of your eye and focus instead on dealing with the plank in his eye, you would have done your part.
But if he chooses to disregard your sensible and helpful suggestion, that becomes his own affair. As a grownup man he must deal with the consequences of his actions. Because the next time he lets slip his anger, he could land up in court. And should this be happening, he should be ever so lucky that the wise magistrate does no more than place him on an online management course anyhow. This is no slap on the wrist, to be sure. A huge favor to both self and community has been done.