I believe it would be a mistake to presume that, because Luke shows in the next few chapters that Rome believes Paul was innocent of the charges brought against him, he means to show Rome as a benevolent or just Empire. It was not, and it certainly was not so toward Christianity during the next few centuries. Nor was it true of Felix, who not only wouldn’t release Paul without receiving a bribe (Acts 24:26), but left Paul’s case unresolved after he was replaced by Festus and sent to Rome to answer charges leveled against him by the Jewish authorities (Acts 24:27).
I believe Luke is and has been emphasizing two matters concerning the Kingdom of God in the life and sufferings of Paul. First, he means to show that, just as Jesus came to his own people but wasn’t embraced by them (John 1:11), so Paul, the Jew and his message, was not received by many Jews of his day, especially the authorities and those loyal to them. Secondly, I believe Luke means to show us through the governors of the Roman Empire, especially the governors of Judea whom Josephus, the Jewish historian, shows were very corrupt, that God works all things together for good in the lives of those who love him and are called to execute his plans for mankind (Romans 8:28).
Paul was sent in protective custody by the tribune, Claudius Lysais and leading Roman official at Jerusalem, to Felix, the governor of Judea who resided at Caesarea (Acts 23:22-35). Felix had Paul guarded in Herod’s palace (Acts 23:35), showing that Paul was not only received as a Roman citizen, but was also regarded as someone of power and influence, i.e. having some wealth. I hardly believe Paul’s status at this time was comparable to that of a homeless man today. Some Christians and critics like to believe Paul was poor, but Luke doesn’t leave us with this impression. Why would Rome bend its military might and political influence to aid a poor, homeless man? The whole idea is preposterous.
Paul’s Roman citizenship implies a noble birth; someone in his family, his father or more likely his grandfather, had aided Rome in such a manner that he was endowed with this honor. Moreover, Paul’s education in Jerusalem also implies family wealth; notice also, that Paul’s nephew was able, through his own influence and station in the Jewish community, to gain valuable information for Paul’s safety (Acts 23:16), and was received by the Roman officials. So, influence of some kind is implied here – that of Paul, his nephew, or more likely that of both.
Luke shows us through James’ statement in Acts 21:24 that he believed Paul had some wealth. I cannot rightly presume that James would regard it proper to take money the gentiles offered for the poor at Jerusalem and spend it for the Temple sacrifices needed by those Jews having a vow. The witnesses Paul had brought with him from the churches of various parts of Europe and Asia were there to monitor and to reply to any suspicion or charges some believers or critics might have had against Paul that the great offering was taken by Paul for his own services to them (cp. Acts 18:3; 20:18, 33-35; 2Corinthians 11:27).
If Paul was poor at any time (cp. 2Corinthians 11:27), it would have been because his activities in Messianic Judaism served to create a breach between him and his father. If this is so, reconciliation would undoubtedly have occurred by this time. Certainly Paul’s nephew felt free to advise Paul of eminent danger. Moreover, the fact that Paul is considered both by James and Felix to have some wealth seems to imply Paul’s noble status. Perhaps Paul’s father had by this time embraced Christianity, or perhaps he died and Paul came into his inheritance; but whatever the reason for a presumed change of status, some wealth and nobility of birth are implied and attributed to Paul in these final chapters of Acts.
 Josephus: Antiquities of the Jews, 20.8.9.