'Key' in the Bible

And they tarried till they were ashamed; and, behold, he opened not the doors of the upper room: therefore they took the key, and opened them , and, behold, their lord was fallen down dead on the earth.

And the key of the house of David will I lay upon his shoulder; and he shall open, and none shall shut; and he shall shut, and none shall open.

Woe unto you lawyers! for ye took away the key of knowledge: ye entered not in yourselves, and them that were entering in ye hindered.

And to the angel of the church in Philadelphia write: These things saith he that is holy, he that is true, he that hath the key of David, he that openeth and none shall shut, and that shutteth and none openeth:

And the fifth angel sounded, and I saw a star from heaven fallen unto the earth: and there was given to him the key of the pit of the abyss.

And I saw an angel coming down out of heaven, having the key of the abyss and a great chain in his hand.