John Calvin on Jeremiah 18:10

Now follows the opposite clause, But if it will do evil before mine eyes, so as not to hear my voice; that is, when a nation has been planted through my kindness, (for this is required by the context,) then I will repent, etc. By this denunciation is meant, that God would tread in the dust those whom he had favored with singular benefits, on account of the abuse made of them; although he had said, “When I promise bountifully and freely to a nation or a kingdom everything that can be wished, except my favor and goodness be rightly received, then I repent of the good done to it.” The meaning is, that the way of pardon is always open, when a sinner turns to God, and that it is in vain for men to boast of God’s promises, except, they in fear and obedience submit themselves to him.

Both these things were necessary; that is, that the Jews should know that God would be entreated if they repented, and that his promises could not be extended to those who were guilty of such gross abuse as a total disregard of his law and his prophets. Then the Prophet mentions here the ordinary course, — that as soon as men repented, they might safely and fully expect good things from God, for he is inclined to mercy; and then, that no nation, however it may excel in gifts, ought to indulge a foolish confidence and to use its present glory as means to despise its giver, for God can take away what he has given. The real import of the whole then is, that we cannot expect to enjoy the benefits which God bestows on us, except we persevere in faithfulness and in the fear of him. It is indeed cmtain that God’s blessings do not depend on worthiness in man; but still he will not have his bounty to be despised, as was the case with the Jews, and at this day it is a common thing in the world. It now follows,--

Jeremiah 18:11-12

11. Now therefore go to, speak to the men of Judah, and to the inhabitants of Jerusalem, saying, Thus saith the LORD; Behold, I frame evil against you, and devise a device against you: return ye now every one from his evil way, and make your ways and your doings good.

11. Et nunc (agedum) dic ad virum Jehudah (hoc est, ad unumquemque,) et incolas Jerusalem, dicendo (alloquere omnes Judaeos et incolas Jerusalem,)sic dicit Jehova, Ecce ego fingo super vos malum, et cogito super vos eogitationem; revertimini igitur quisque a via sua mala, et rectas facite vias vestras et studia vestra.

12. And they said, There is no hope: but we will walk after our own devices, and we will every one do the imagination of his evil heart.

12. Et dixerunt, Actum est; quia post cogitationes nostras ambulabimus, et quisque pravitatem cordis sui mali faciemus.