Jeremiah
Jeremiah 9:14ESV·traditional attribution

but have stubbornly followed their own hearts and have gone after the Baals, as their fathers taught them.

John Calvin Reformed @genevareformer

He then adds, And they have walked after the hardiness, or obstinacy, or imaginations, of their own heart See Note on Jeremiah 3:17, 18. He opposes the imaginations, or hardness of the heart, to the voice of God, as we find in other places, where contrary things are stilted, that is, what men’s minds devise, and what God shews by his word to be right...

Matthew Henry Presbyterian @wholebiblehenry

Two things the prophet designs, in these verses, with reference to the approaching destruction of Judah and Jerusalem: - 1. To convince people of the justice of God in it, that they had by sin brought it upon themselves and that therefore they had no reason to quarrel with God, who did them no wrong at all, but a great deal of reason to fall...

Commenting on Jeremiah 9:12-22

John Gill Reformed Baptist @doctorgill

But have walked after the imagination of their own heart,.... What their own hearts devised, chose, and were best pleased with; See Gill on Jer 7:24, and after Baalim; the idols of the Gentiles; these they served and worshipped, and not the true God: which their fathers taught them; which was so far from excusing them, that it was an aggravation of their sin, that...