Flint

abounds in all the plains and valleys of the wilderness of the
forty years' wanderings. In Isa. 50:7 and Ezek. 3:9 the
expressions, where the word is used, means that the "Messiah
would be firm and resolute amidst all contempt and scorn which
he would meet; that he had made up his mind to endure it, and
would not shrink from any kind or degree of suffering which
would be necessary to accomplish the great work in which he was
engaged." (Compare Ezek. 3:8, 9.) The words "like a flint" are
used with reference to the hoofs of horses (Isa. 5:28).