Who renews the quarreling and feuding between the families in act 3 scene 1 and why?

Answer 1

Well, it's Tybalt basically, and he is not so much after Montagues as after one Montague, namely Romeo. "Here comes my man" he says.

The interesting thing is that Tybalt is not a Capulet. His auntie is married to a Capulet is all. He has no stake in the feud--he just likes to fight. Mercutio isn't a Montague either, since he is related to the Prince. And if you notice, during the trial scene at the end of act 3 scene 1, it is Mrs. Capulet, who is only a Capulet by marriage, who is trying to stir up the feud again, since Tybalt is her relative. Capulet hangs back, because Tybalt is not his relative and he doesn't like him much (think about how he talked to him in Act 1 Scene 5).

Answer 2

In Act 3, Scene 1 of "Romeo and Juliet," it is Tybalt who renews the quarrel between the families by challenging Romeo to a duel. Tybalt does this because he is angered by Romeo's presence at the Capulet party and refuses to tolerate a Montague in their midst. This provocation ultimately leads to a tragic chain of events that result in the deaths of Mercutio and Tybalt.