Jesus declares Himself to be the one who holds the key of David. He has the authority to open and to shut, making Him the one who controls entrance to the royal palace, the place where the authority of the kingdom concentrates.
The language of this text is based on Isaiah 22:22. Sennacherib of Assyria was attacking Jerusalem. The leaders of the nation had gathered weapons, shored up the city walls, and secured the water supply of the city. But God criticized their work because in all their preparations they never asked Him for help. Instead, when they realized that their situation was hopeless, they decided to party and enjoy what few resources they had left before death overtook them (verses 1-13).
Shebna, who was in charge of the royal palace, proved to be as materialistic as the people, commissioning a spectacular grave to be carved out for himself in a prominent place (verses 15, 16). The Lord deposed him from his position and gave the key of David to Eliakim, the son of Hilkiah, instead (verses 17-21). From then on Eliakim would be the one with the authority to open and shut the doors of the kingdom (verse 22).
In the American government we would call the position described here as chief of staff. This position came to the attention of the American people during the Watergate crisis of 1973-1974. H. R. Haldeman, President Nixon's chief of staff, had full control of the president's schedule. He decided who could get in to see the president and who could not. If he didn't like someone, that person would never have access to the president unless the president intervened personally!
Many people have the idea that the top leaders of American government meet with the president on a daily basis. Actually very few have that privilege. Above all others the chief of staff is in constant contact with the president. If he wishes and the president allows, the chief of staff can become the most powerful and influential position in the U. S. government, even though the individual is neither elected by the people nor ratified by Congress.
As in Smyrna, the members of the church at Philadelphia experienced conflict in relation to the local synagogue. It is likely that the Christians of Philadelphia found themselves disfellowshipped from the synagogue, and they may have questioned whether they had lost their place in heaven as well. Jesus assures them that He, and He alone, decided who enters the temple of God. As long as they remain in relationship with Him, their position with God is secure.
Lord, I treasure the access I have with You in Christ. Help me to serve You today with joy and confidence, knowing that Jesus has set before me an open door.