Student in my class gets attacked

[Vio]

Im just coming back from training tonight. What a session it was.
Theres this guy who hasnt been training for about 5 months now, hes a good friend of mine as well, he says he's been concentrating on his studies.
So today he just came in to train.
After the class the guy had a discussion with our sifu, he tells sifu that since he's been away he tried a thai boxing class and that the wing chun techniques worked well for him.

Then sifu tells him he should work on his forms its time for him to move onto level 2 (level 2 = chum kui, 3 = Bui jee) . The guy replies saying ive been training wing chun just as long as some of the level 2s. He goes on to say hes better than some of the level 2 and 3s.

Sifu says "ok then", tells him to free spar with a level 3 student Sifu picks one of his his top students. He does ok but he ultimately loses the match, this level 3 is the english full contact champion.

Then hes asked by sifu to spar with a level 2, you can see the guy isnt too fit , he's now breathing heavy and cant even lift his leg up to black kicks. He's too tired to fight but he fares better with the level 2.

After the fight sifu starts swearing at this guy and says how his students should have beat him even more. The guy apologises to both seniors.

Then sifu gets up with his eyes redened he's obviously very angry now of a sudden, says how can you just come in here and just say that you're better than us. Then rushes in and attacks the guy. Our sifu isnt a small guy he wells over 300 pounds. The guy keeps yelling "Sifu i said i was sorry", but its no use. Sifu says are you going going to defend yourself, he nods his head then says "no, sifu I had so much respect for you, i looked up to you.".

Sifu just walked out after the incident. I dunno whether the guy should come back or not. I dunno if this guy did anything really wrong. Its kinda surprising that sifu didnt consider the "his" student even though he's been training him for over 3yrs now, sad.