December 20: O Clavis David, O Key of David

O Key of David, o royal Power of Israel,

controlling at your will the gate of heaven:

Come, break down the prison walls of death

for those who dwell in darkness 
and the shadow of death;

and lead your captive people into freedom.

Revelation 3: 7

Isaiah 22: 22

Jeremiah 13: 13, 51: 19

Matthew 4: 16, 16: 19

Luke 1: 79

...How much time has been wasted in the futile search for keys, how many hours poured into rearranging schedules when they go missing?

Knowing how crucial the key can be helps us appreciate how, of all the antiphons, this one is most clearly realized in Jesus. For many people, he was key to liberation, but one example will suffice: a story told in Luke 13:10-17. To a woman who had been bent double for 18 years, Jesus called, "You are free of your infirmity!" As her spine straightened, she praised God. And those who were listening carefully might have heard a key clink in a rusty lock.

She is not unique. Over and over, Jesus calls people to freedom and friendship. ...
 (by Kathy Coffey in the December 1999 Catholic Update "O Come, O Come Emmanuel")