20 “‘At that time I will summon my servant Eliakim, son of Hilkiah. 21 I will put your robe on him, tie your belt around him, and transfer your authority to him. He will become a protector of the residents of Jerusalem and of the people of Judah. 22 I will place the key to the house of David on his shoulder. When he opens the door, no one can close it; when he closes the door, no one can open it. 23 I will fasten him like a peg into a solid place; he will bring honor and respect to his father’s family. 24 His father’s family will gain increasing prominence because of him, including the offspring and the offshoots. All the small containers, including the bowls and all the jars, will hang from this peg.’
4 But you have a few individuals in Sardis who have not stained their clothes, and they will walk with me dressed in white because they are worthy. 5 The one who conquers will be dressed like them in white clothing, and I will never erase his name from the book of life, but will declare his name before my Father and before his angels. 6 The one who has an ear had better hear what the Spirit says to the churches.’ 7 “To the angel of the church in Philadelphia write the following: “This is the solemn pronouncement of the Holy One, the True One, who holds the key of David, who opens doors no one can shut, and shuts doors no one can open: 8 ‘I know your deeds. (Look! I have put in front of you an open door that no one can shut.) I know that you have little strength, but you have obeyed my word and have not denied my name.
Notes and References
"... The House and court circle of David play a key role in Samuel-Kings and Chronicles, and later in Zechariah 12:7-13:1. Also, the New Testament frequently considers the Church as the New Temple; and the old Temple was the twin of the palace of the king - 2 Samuel 7:11-13 (the ambivalent 'house'); 1 Kings 8:20. On his throne to the south of the Temple the Davidid literally sat at the-right band of God. After Peter acknowledges Jesus as the Messiah and (Davidic?) Son of God, he is assured, 'I will give you the keys of the kingdom of heaven' (Matthew 16:19). Most commentators relate this to the giving of the key to the house of David to Eliakim in Isaiah 22:22. But the fuller meaning of the passage is lost if it is not sensed that Jesus is here acting as the Son of David restoring the fallen tent of bis ancestors (Amos 9:11; also, Acts 15:13-18). and looking to the new Temple built of living stones. The earnestness of bis werk for the latter appears in the fact that he was executed for presuming tobe the King of the Jews and master of the Temple, as the following paragraphs show. lt is not eisegesis to associate the key of David with the new Temple or ekklesia. Precisely this coupling is found in Revelation 3:7 and 12. in a context of keeping the commandments of Jesus (verses 8-10; compare Matthew 16:19) ..."
Nolan, Brian M. The Royal Son of God: The Christology of Matthew 1-2 in the Setting of the Gospel (p. 180) Vandenhoeck & Ruprecht, 1979