Jesus points out to the church in Philadelphia that he has given to them an open door. What does he mean by that? He is referring to his use of the key in the previous verse that symbolised his authority. Does he mean by his door that they have access to heaven or entrance into his kingdom or does he mean that they have access into the community around them?
They may have been barred from areas of life in the city. The Jews may have stopped them from attending the synagogue and the city authorities may have prevented them from having opportunities for work. Whatever doors were closed by their human opponents, they could not close the door that Jesus kept open.
The implication is that they were meant to go through the door and use whatever the access was that was available to them. They could go into the presence of Jesus in prayer and they could enter the community with the gospel. It looks as if Jesus is describing an entrance that no power on earth could ever close, which would indicate that the open door is entrance into the presence of God at any time.
This would have been a great encouragement from Jesus to a church that was regarded as insignificant in the community. They were small in number probably and had little influence in the city. Yet they had remained true to him, even when they were opposed by others.
The opposition to them seems to have been led by the Jews, which was a common experience for the New Testament church. Because Jesus has the key of authority he is able to deal with that situation. He informs the church there that on the Day of Judgement they will be recognised as belonging to him, with that recognition including their opponents bowing down before them. In the Old Testament, it was predicted that Gentiles would bow to God’s people, and no doubt the Jewish opponents of the church had assumed that the church would be among the Gentiles. Jesus reveals that those Jews would be among the Gentiles who would acknowledge the place that Christians will have through their connection to Jesus. So he gives them encouragement from their future blessings as well.