Jeremiah 17:1
The sin of Judah is written with a pen of iron, and with the point of a diamond: it is graven upon the table of their heart, and upon the horns of your altars;
Cross-reference
Jeremiah 2:22
Parallel
Jeremiah 2:22 says iniquity is marked before God despite washing — a parallel image of sin's permanence, like engraving with diamond.
Job 19:24
Parallel
In Job 19:24, the same imagery of iron pen and engraving appears — Job longs for permanent record, Jeremiah laments sin's permanence.
Proverbs 3:3
Contrast
In Proverbs 3:3, love and faithfulness are to be written on the heart — opposite of sin engraved there in Jeremiah.
Proverbs 7:3
Contrast
In Proverbs 7:3, commandments are written on the heart — contrasting with sin's engraving in Jeremiah.
Ezekiel 14:3
Parallel
Ezekiel 14:3 speaks of idols set up in the heart — a direct parallel to sin engraved on the heart's tablet in the main verse.
2 Corinthians 3:3
Allusion
In 2 Corinthians 3:3, the Spirit writes Christ's letter on hearts — a new covenant contrast to sin engraved on hearts.