'Flint' in the Bible
So Zipporah took a flint, cut off her son's foreskin, and threw it at Moses' feet. Then she said, "You are a bridegroom of blood to me!"
Who led thee through that great and terrible wilderness, wherein were fiery serpents, and scorpions, and drought, where there was no water; who brought thee forth water out of the rock of flint;
He mounted him on a high place above the earth, feeding him from the produce of the field. He nourished him with honey from the rock and with oil from the flint rock,
At that time the Lord said to Joshua, "Make flint knives and circumcise the Israelite men again."
So Joshua made flint knives and circumcised the Israelite men at Gibeath-haaraloth.
The miner strikes the flint and transforms the mountains at [their] foundations.
Which turned the rock into a standing water, the flint into a fountain of waters.
Whose arrows are sharp, and all their bows bent, their horses' hoofs shall be counted like flint, and their wheels like a whirlwind:
For the Lord GOD will help me; therefore shall I not be confounded: therefore have I set my face like a flint, and I know that I shall not be ashamed.
As an adamant harder than flint have I made thy forehead: fear them not, neither be dismayed at their looks, though they be a rebellious house.
"They made their hearts like flint so that they could not hear the law and the words which the LORD of hosts had sent by His Spirit through the former prophets; therefore great wrath came from the LORD of hosts.