O Clavis David
O Key of David and sceptre of the House of Israel;
you open and no one can shut;
you shut and no one can open:
Come and lead the prisoners from the prison house,
those who dwell in darkness and the shadow of death.
Isaiah, xxii, 22:
And the key of the house of David will I lay upon his shoulder; so he shall open, and none shall shut; and he shall shut, and none shall open.
Revelation, iii, 7:
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 no man shutteth; and shutteth, and no man openeth;
Isaiah, xlii, 7:
To open the blind eyes, to bring out the prisoners from the prison, and them that sit in darkness out of the prison house.
(For explanation, see here.)