Specifically, on this way to Jerusalem, it appears that the Holy Spirit warns Paul twice not to go:
Acts 21.1-6, 10-11So, does Paul disobey the Holy Spirit in going to Jerusalem anyway?
When we had parted from them and set sail, we came by a straight course to Cos, and the next day to Rhodes, and from there to Patara. When we found a ship bound for Phoenicia, we went on board and set sail. We came in sight of Cyprus; and leaving it on our left, we sailed to Syria and landed at Tyre, because the ship was to unload its cargo there. We looked up the disciples and stayed there for seven days. Through the Spirit they told Paul not to go on to Jerusalem. When our days there were ended, we left and proceeded on our journey; and all of them, with wives and children, escorted us outside the city. There we knelt down on the beach and prayed and said farewell to one another. Then we went on board the ship, and they returned home...
While we were staying there for several days, a prophet named Agabus came down from Judea. He came to us and took Paul’s belt, bound his own feet and hands with it, and said, “Thus says the Holy Spirit, ‘This is the way the Jews in Jerusalem will bind the man who owns this belt and will hand him over to the Gentiles.’”
A chapter earlier, Paul does seem to know, because of the the Holy Spirit, that he is going to be arrested. And he also shares that he feels compelled by the Spirit to go to Jerusalem. Paul, saying goodbye to the Ephesian elders:
Acts 20.22-23So we see the paradox. In Acts 20 Paul says the Spirit is sending him to Jerusalem. Yet in Acts 21, he gets warnings from the Spirit not to go to Jerusalem.
And now, as a captive to the Spirit, I am on my way to Jerusalem, not knowing what will happen to me there, except that the Holy Spirit testifies to me in every city that imprisonment and persecutions are waiting for me.
What to make of all this?
Opinions seem to differ on how to reconcile these passages. But one thing that does seem clear is that while the Spirit might give Paul a warning, Paul is still free to follow his course of action. The Spirit seems to be giving Paul information to make discernments, but is still leaving it up to Paul to make the choices, even very hard choices.
I find this interesting because, in my world, a lot of Christians speak of God "closing" and "opening" doors. On that reading, it seems clear that the Spirit was trying to "close the door" on Paul's return to Jerusalem. And yet, Paul ignored those signs and opened the door. And that choice is a faithful, if costly, choice.
All that to say, warnings and bad omens, at least in Acts, aren't necessarily signs a "closed door" from God. Warnings and bad omens seem to be more about information that about what decision to make. The Spirit might give you a warning, but that doesn't necessarily mean you shouldn't keep going. The warning is less about changing your mind than preparing you for the maelstrom to come.