For thus saith the LORD, Thy bruise is incurable, and thy wound is grievous.

Wesley's Notes

30:12 For - They had sinned to that degree that God had resolved they should go into captivity.

Jamieson-Fausset-Brown Bible Commentary

12. The desperate circumstances of the Jews are here represented as an incurable wound. Their sin is so grievous that their hope of the punishment (their exile) soon coming to an end is vain (Jer 8:22; 15:18; 2Ch 36:16).

Matthew Henry's Concise Commentary

30:12-17 When God is against a people, who will be for them? Who can be for them, so as to do them any kindness? Incurable griefs are owing to incurable lusts. Yet, though the captives suffered justly, and could not help themselves, the Lord intended to appear for them, and to punish their oppressors; and he will still do so. But every effort to heal ourselves must prove fruitless, so long as we neglect the heavenly Advocate and sanctifying Spirit. The dealings of His grace with every true convert, and every returning backslider, are the same in effect as his proceedings to the Jews.