Alternatively, he could have said "I've got a gun tucked in the back of my jeans and I'm going to use it" or words to that effect, which justifies (at least some of) the beating.
Or he could have said "I'm going pull this knife out of my pocket and stab your horse in the face and then urinate on it whilst laughing at you for having a horse which has been stabbed and urinated on".
That would justify the use of force to restrain him, not to beat him to a pulp