John Calvin Commentary Isaiah 30:9

"For it is a rebellious people, lying children, children that will not hear the law of Jehovah;" — Isaiah 30:9 (ASV)

For this is a rebellious people. The word for or because points to the explanation of what has already been said. The Prophet explains what the Lord intends to declare to posterity: namely, that the perverseness of this nation is desperate, because they cannot submit to being restrained by any doctrine.

It can be inferred from their loud boasting that the honorable title of “the people” wounded to the quick the hearts of both the common people and the nobles. For they boasted that they were the holy and elect seed of Abraham, as if God’s adoption were a veil to cover the grossest crimes. But God commands that their crimes must nevertheless be brought to light and openly proclaimed.

Who refuse to hear the law of Jehovah. By accusing them of this, he points out the source of all evils: namely, contempt of the word, which reveals their wickedness and their contempt of God Himself. For it is futile to pretend that they worship God when they are disobedient to His word.

Isaiah likewise aggravates their guilt by saying that they reject the remedy that doctrine offers for curing their diseases. For this reason, he calls them not only “rebellious” and untameable or abandoned, but also liars or treacherous persons.

For those who refuse to obey the word of God openly revolt against Him, as if they could not endure His authority. At the same time, they show that they are given over to vanity and the delusions of Satan, so that they take no pleasure in sincerity.