What does Tybalt mean in line 53-58

My copy has the following quote in these lines,

I can tell by his voice that this man is a Montague. (to his PAGE) Get me my sword, boy.—What, does this peasant dare to come here with his face covered by a mask to sneer at and scorn our celebration? Now, by the honor of our family, I do not consider it a crime to kill him.

 Basically Tybalt has spotted Romeo at the Capulet party and thinks his presence is offensive to them.