9 By this therefore shall the iniquity of Jacob be purged; and this is all the fruit to take away his sin; when he maketh all the stones of the altar as chalkstones that are beaten in sunder, the groves and images  shall not stand up.
9 By this, then, will Jacob's guilt be atoned for, and this will be the full fruit of the removal of his sin: When he makes all the altar stones to be like limestone crushed to pieces, no Asherah poles
9 Therefore by this the guilt of Jacob will be atoned for, and this will be the full fruit of the removal of his sin:
9 But the good news is that through this experience Jacob's guilt was taken away. The evidence that his sin is removed will be this: He will tear down the alien altars, take them apart stone by stone, And then crush the stones into gravel and clean out all the sex-and-religion shrines.
9 Therefore by this the iniquity of Jacob will be covered; And this is all the fruit of taking away his sin: When he makes all the stones of the altar Like chalkstones that are beaten to dust, Wooden images and incense altars shall not stand.
9 The Lord did this to purge Israel's wickedness, to take away all her sin. As a result, all the pagan altars will be crushed to dust. No Asherah pole or pagan shrine will be left standing.
Matthew Henry's Commentary on Isaiah 27:9
Commentary on Isaiah 27:6-13
(Read Isaiah 27:6-13)
In the days of the gospel, the latter days, the gospel church shall be more firmly fixed than the Jewish church, and shall spread further. May our souls be continually watered and kept, that we may abound in the fruits of the Spirit, in all goodness, righteousness, and truth. The Jews yet are kept a separate and a numerous people; they have not been rooted out as those who slew them. The condition of that nation, through so many ages, forms a certain proof of the Divine origin of the Scriptures; and the Jews live amongst us, a continued warning against sin. But though winds are ever so rough, ever so high, God can say to them, Peace, be still. And though God will afflict his people, yet he will make their afflictions to work for the good of their souls. According to this promise, since the captivity in Babylon, no people have shown such hatred to idols and idolatry as the Jews. And to all God's people, the design of affliction is to part between them and sin. The affliction has done us good, when we keep at a distance from the occasions of sin, and use care that we may not be tempted to it. Jerusalem had been defended by grace and the Divine protection; but when God withdrew, she was left like a wilderness. This has awfully come to pass. And this is a figure of the deplorable state of the vineyard, the church, when it brought forth wild grapes. Sinners flatter themselves they shall not be dealt with severely, because God is merciful, and is their Maker. We see how weak those pleas will be. Verses 12,13, seem to predict the restoration of the Jews after the Babylonish captivity, and their recovery from their present dispersion. This is further applicable to the preaching of the gospel, by which sinners are gathered into the grace of God; the gospel proclaims the acceptable year of the Lord. Those gathered by the sounding of the gospel trumpet, are brought in to worship God, and added to the church; and the last trumpet will gather the saints together.