Abinadi can tell that his words are effecting Noah and his priests. He specifically notes that "it cuts you to your hearts because I tell you the truth…" The effect of hearing the truth on those who have justified their actions is to bring back the sharp recognition of the pain of sin. Because that is an uncomfortable feeling, and exposes the coverings placed over the sin, anger is a very typical response.
In order to feel this pain, however, their hearts had to be capable of being touched by the spirit, otherwise they could not have recognized that they were personally in conflict with message Abinadi was delivering. This pain is the first step to an ability to repent, but it clearly does not guarantee repentance. Of all of the priests who were pierced by this awakening of the spirit, only one is known to have accepted the pain for what it was and repented.