'Staff' in the Bible

Moreover he said unto me, Son of man, behold, I will break the staff of bread in Jerusalem: and they shall eat bread by weight, and with fearfulness; and they shall drink water by measure, and in dismay:

when I shall send upon them the evil arrows of famine, that are for destruction, which I will send to destroy you: and I will increase the famine upon you, and will break your staff of bread;

Son of man, when a land sinneth against me by committing a trespass, and I stretch out my hand upon it, and break the staff of the bread thereof, and send famine upon it, and cut off from it man and beast;

And all the inhabitants of Egypt shall know that I am Jehovah, because they have been a staff of reed to the house of Israel.