Abinadi is responding to the question he posed to the priests in Mosiah 12:31. Their answer was incorrect because it excluded the saving power of the atonement. It assumed the law alone was enough. Abinadi corrects them as did the author of Hebrews, For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect…For it is not possible that the blood of bulls and of goats should take away sins (Heb 10:1,4).