Mike,

Acts 10 is the chapter after Paul's conversion.

Peter, as a result of a vision, went to Cornelius, a Gentile, preached, and the Holy Ghost fell on all that heard him.

However, Peter did not preach differently than he had been, previously.

So, was Cornelius then part of the kingdom, although a Gentile, and therefore not a part of the mystery church?

I looked in the Grace Ambassadors resources, and read:

https://graceambassadors.com/midacts/did-cornelius-learn-the-mystery


And also listened to:

https://graceambassadors.com/audio/mad-objections-04

But, unless I missed it, I don't remember if this was addressed distinctly, i.e. was Cornelius then part of the kingdom?

Let me know what you think.