Jeremiah 17:1

Graven — Nor is it a thing done in secret, but it is engraven upon the horns of their altars. God's altar was four — square, and at each corner there was a rising part made of brass, these were called the horns of the altar. Now their sin is said to be engraven upon the horns of the altar, because the blood of the sacrifices which they offered to idols was sprinkled there, or because their altars had some inscription upon them, declaring to what idol that altar was consecrated.