Audio commentary on this verse

Note 2 at Ro 2:21: The Jews took pride in their keeping of the Law, but no Jews could boast that they had kept the Law perfectly (see note 4 at Mr 10:20). "All have sinned, and come short of the glory of God" (Ro 3:23). Paul highlighted three areas where they boasted of their own holiness, but he revealed that they were actually sinners in these very things.

They boasted that they didn't steal, but Paul revealed that they did steal. Jesus also rebuked the Pharisees for stealing. This was not the typical type of theft, but what we would call "white-collar crime."

Paul said that they were adulterers, even though they prided themselves on not committing adultery. They were guilty of spiritual adultery if nothing else (Jas 4:4), and Jesus had revealed that adultery was also a sin of the heart, even if there was no action (Mt 5:28).

They also thought they were not idolatrous, but Paul convicted them on this count also. He used the word "sacrilege". This referred to them being temple robbers, thereby making direct reference to their covetousness, which is idolatry (Col 3:5).

Therefore, even though they had a form of godliness, they were sinners just like the Gentiles, and their hypocrisy gave the Gentiles a reason to blaspheme God. This led Paul to proclaim that the Jews' claim to some kind of special covenant with God was made void through their breaking of the Law. In the third chapter of Romans, he went on to draw the conclusion that everyone, Jew and Gentile, is in the same condition of sin and needs the same salvation through Christ.