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; 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;
The sin of Judah is portrayed as cut deeply and permanently, as with an iron pen and a diamond point, engraved upon the table of the heart and upon the horns of the altars. It is a divine denunciation of wickedness, directed with special force to those entrusted with positions of trust. The engraving points to an individual reckoning for every person before the heavenly courts, where salvation depends on possessing a character that God can approve, a character marked by integrity, truthfulness, and unwavering steadfastness to principle.
What is written on the heart is tested and brought to light by the treatment of the poor and suffering, whom God places among His people for the very purpose of revealing what is within. With a permanence like iron writing upon stone, the principle must be made firmly settled, rooted and grounded in the conscience, that justice is never to be violated and mercy is never to be neglected. Whoever disregards mercy, compassion, righteousness, kindness, and courtesy, who neglects the poor and turns away from suffering humanity, dishonors God. Such a course brings him no benefit, but its result is reflected back upon himself, and by so conducting himself he puts himself where God cannot cooperate with him in the development of character.