Acts 21:4 (NASB)
After looking up the disciples, we stayed there seven days; and they kept telling Paul through the Spirit not to set foot in Jerusalem.

- Interesting warning in light of the fact that before long, we know, Paul ends up going purposefully down to Jerusalem...

Acts 21:13 (NASB)
Then Paul answered, "What are you doing, weeping and breaking my heart? For I am ready not only to be bound, but even to die at Jerusalem for the name of the Lord Jesus."

And since he would not be persuaded, we fell silent, remarking, "The will of the Lord be done!"

After these days we got ready and started on our way up to Jerusalem.

...

Acts 21:20 (NASB)
... "You see, brother, how many thousands there are among the Jews of those who have believed, and they are all zealous for the Law; and they have been told about you, that you are teaching all the Jews who are among the Gentiles to forsake Moses, telling them not to circumcise their children nor to walk according to the customs.

- The rift is growing over the issue of "religious traditions" and pious practice. Apparently Jewish followers of Jesus in Jerusalem are offended that Paul might be teaching that the traditions of Moses no longer are required for salvation. Which he probably was. The full implications of Christ's sacrifice and salvation by grace alone are clear to Paul, but not so all Christians.

This sort of controversy continues until today, often in a similar spirit of anger and righteous indignation. The warning of Jesus comes to mind, that one day his disciples would be killed by people thinking they were doing this for God.