'Rust' in the Bible

"This is what the Lord GOD says: "How terrible it is for that blood-filled city, to the pot whose rust remains in it, whose rust won't come off. Empty it one piece at a time. Don't let a lot fall on it.

Make the pot stand empty on the coals until its bronze glows red, its rust can be scoured off, and its dross completely removed.

The pot wearies me, but its thick rust won't come off, even with fire.

"Stop storing up treasures for yourselves on earth, where moths and rust destroy and where thieves break in and steal.

But keep on storing up treasures for yourselves in heaven, where moths and rust do not destroy and where thieves do not break in and steal,