Matthew Henry Commentary Jeremiah 17:1-4

"The sin of Judah is written with a pen of iron, [and] with the point of a diamond: it is graven upon the tablet of their heart, and upon the horns of your altars; whilst their children remember their altars and their Asherim by the green trees upon the high hills. O my mountain in the field, I will give thy substance and all thy treasures for a spoil, [and] thy high places, because of sin, throughout all thy borders. And thou, even of thyself, shalt discontinue from thy heritage that I gave thee; and I will cause thee to serve thine enemies in the land which thou knowest not: for ye have kindled a fire in mine anger which shall burn for ever." — Jeremiah 17:1-4 (ASV)

The sins which men commit make little impression on their minds, yet every sin is marked in the book of God; they are all so engraved upon the table of the heart that they will all be remembered by the conscience. That which is engraved in the heart will become plain in the life; men's actions show the desires and purposes of their hearts.

How great is our need to humble ourselves before God, who are so vile in His sight! How we should depend on His mercy and grace, begging God to search and prove us; not to allow us to be deceived by our own hearts, but to create in us a clean and holy nature by His Spirit!