Bible Verses About Adamant

I haue made thy forehead as the adamant, and harder then the flint: feare them not therefore, neither be afraid at their lookes: for they are a rebellious house.

Yea, they made their hearts as an adamant stone, least they should heare the Lawe and the wordes which the Lord of hostes sent in his spirit by the ministerie of ye former Prophets: therefore came a great wrath from the Lord of hostes.