Charles Ellicott Commentary Isaiah 29:13

"And the Lord said, Forasmuch as this people draw nigh [unto me], and with their mouth and with their lips to honor me, but have removed their heart far from me, and their fear of me is a commandment of men which hath been taught [them];" — Isaiah 29:13 (ASV)

Therefore the Lord said ... —We pass from the effect to the cause. The blind stupor was the outcome of a long hypocrisy. Lip-homage and an estranged heart had been the characteristics of the religious life of Israel, and they could bear no other fruit.

Their fear toward me ... —The words point to what we may call an anticipated Pharisaism. Side by side with the great commandments of the Law and with the incisive teaching of the prophets, a traditional system of ethics and religion was growing up even then, based upon wrong principles, ending in dishonest casuistry and formal devotion. Commentaries even then were darkening counsel by words without knowledge, as they did in the Mishna and the Gemara of the later days of Judaism (Matthew 15:3; Mark 7:6).