'Key' in the Bible

And they waited so long they became embarrassed because he did not open the doors of the upper room. So they took the key and opened [the doors], and there their lord was lying on the ground dead.

And I will put the key of the house of David on his shoulder, and he shall open and no one [will be able to] shut; and he shall shut and no one [will be able to] open.

Woe to you, legal experts, because you have taken away the key to knowledge! You did not enter yourselves, and you hindered those who were entering!"

"And to the angel of the church in Philadelphia write: "This is what the holy one, the true one, the one who has the key of David, the one who opens and no one can shut, and who shuts and no one can open, says:

And the fifth angel blew the trumpet, and I saw a star that had fallen from heaven to the earth, and the key of the shaft of the abyss was given to him.

And I saw an angel descending from heaven, holding the key of the abyss and a great chain in his hand.