He said the Curia - the administrative pinnacle of the Roman Catholic Church - was suffering from 15 "ailments", which he wanted cured in the New Year.
Pope Francis - the first Latin American pontiff - also criticised "those who look obsessively at their own image".
He has demanded reform of the Curia.
There was silence at the end of the Pope's speech.
Addressing the Curia on Monday, Pope Francis said some power-hungry clerics were guilty of "cold-bloodedly killing the reputation of their own colleagues and brothers".
The Pope says the Church elite must reach out to poor and vulnerable worshippers
He compared the performance of the church's civil servants to that of an orchestra playing "out of tune" because they fail to collaborate and have no team spirit.