And the heaven over your heads will be brass, and the earth under you hard as iron.

Because I saw that your heart was hard, and that your neck was an iron cord, and your brow brass;

Your shoes will be iron and brass; and as your days, so may your work be.

For see, this day have I made you a walled town, and an iron pillar, and walls of brass, against all the land, against the kings of Judah, against its captains, against its priests, and against the people of the land.

Up! and let the grain be crushed, O daughter of Zion, for I will make your horn iron and your feet brass, and a number of peoples will be broken by you, and you will give up their increase to the Lord and their wealth to the Lord of all the earth.

And they had breastplates like iron, and the sound of their wings was as the sound of carriages, like an army of horses rushing to the fight.

And the fourth kingdom will be strong as iron: because, as all things are broken and overcome by iron, so it will have the power of crushing and smashing down all the earth.

And as you saw the feet and toes, part of potter's work and part of iron, there will be a division in the kingdom; but there will be some of the strength of iron in it, because you saw the iron mixed with the potter's earth.

Iron makes iron sharp; so a man makes sharp his friend.