Revelation 3:8 See, I have set before you an open door, and no one can shut it.

I always thought the church of the open door was the church age of missionary expansion.
Perhaps this church is through the 20th century when the Gospel was no longer restricted to in-person church service or missionary service.
With the invention of the radio came around-the-clock effort to spread the message of Christ.
Preachers, pastors, teachers, and evangelists could go to their local radio station and get the message out to the masses.
Tape recording allowed the message to be recorded today and played back tonight.
Shortwave sent the same message to foreign lands in different languages.
Along came TV and the televangelist.
I know many of them have soured the idea but many others were true to the faith and cared for the souls of their listeners.
Being in Christian radio I have been part of this open door expansion since 1986.
With Covid, we found our church using live streaming to “broadcast” our services on social media, which is another open door.
However, it is a door the Lord will shut one day.
We need to take advantage of the times and step through the doorway and share the Gospel with whosoever.