Francis "offends" Danforth by questioning the findings of the court.  When Francis Nurse enters the court, he enters with a petition of 91 signatures that speak to the character of his wife, Rebecca, Giles Corey's wife, as well as Elizabeth Proctor.  At the same time, Nurse questions the accusations, in general, and the girls who are making them.  While he does not carry himself in a disrespectful manner, the fact that he seeks to speak out against the court findings in the name of the petition and the signatures represents an affront to Danforth.  The Deputy Governor's reaction to the petition reflects how offended he actually is.  Danforth refuses to have anyone speak out against the findings of the court.  Danforth believes that any question is a personal attack on the court and what the court's purpose is.  In this, Danforth takes offense to what Francis Nurse presents.  It is for this reason that Danforth wishes to question the 91 people who have signed the petition, indicating that those who question the court will have their own reckoning in front of the court.  Danforth does this to prevent any questioning of his court and his court's findings.