Revelation 3:6-8

6“Anyone with ears to hear must listen to the Spirit and understand what he is saying to the churches.

7“Write this letter to the angel of the church in Philadelphia. This is the message from the one who is holy and true, the one who has the key of David. What he opens, no one can close; and what he closes, no one can open:

8“I know all the things you do, and I have opened a door for you that no one can close. You have little strength, yet you obeyed my word and did not deny me.