Charles Ellicott Commentary Matthew 23:28

"Even so ye also outwardly appear righteous unto men, but inwardly ye are full of hypocrisy and iniquity." — Matthew 23:28 (ASV)

Even so you also... — We find a similar image in the words of the Maccabean prince, Alexander Jannæus, who on his death-bed warned his wife to beware of “men who were painted Pharisees, expecting the reward of Phinehas, while their works were the works of Zimri.”

Iniquity — A better translation is lawlessness, meaning a reckless disregard of the very Law they professed to interpret.