Albert Barnes' Notes on the Whole Bible - Romans 2:19
And art confident - This expression denotes the full assurance of the Jew that he was superior in knowledge to all other people. It is a remarkable fact that the Jews put the fullest confidence in their religion. Though proud, wicked, and hypocritical, yet they were not speculative infidels. It was one of their characteristics, evinced through all their history, that they had the fullest assurance that God was the author of their institutions, and that their religion was his appointment.A guide... read more
The Pulpit Commentary - Romans 2:19-20
And art confident that thou thyself art a guide of the blind, a light of them which are in darkness, an instructor of the foolish, a teacher of babes, having the form of knowledge and of the truth in the Law . Here the form ( μόρφωσις ) does not mean the mere outward show, but the real representation in concrete form of knowledge and truth. The Jew had that; and the Law itself is by no means disparaged because the Jew presumed on it without keeping it (cf. Romans 7:12 ). read more