Why Antony mock conspirators by honourable men

Brutus had asked Antony not to speak ill of the conspirators. So, keeping with that condition he called them 'honourable men'. However, as he continues his speech he tells the crowd about Caesar's greatness and the plan about his assassination. In order to instigate the crowd to a mob, he repeatedly used the phrase 'honourable men' in an ironical way, referring indirectly to the conspirators. The crowd felt angry when they heard him calling them honourable and this led to their hatred towards the conspirators.