Acts ends with the words: He lived there two whole years at his own expense, and welcomed all who came to him, proclaiming the kingdom of God and teaching about the Lord Jesus Christ with all boldness and without hindrance.
What happened after the two years? What happened at the trial before Caesar? Was Paul released or killed? Did Luke run out of time to write an ending? The answer is clear in the quote below. Some say Acts is the “Acts of the Apostles”, others the “Acts of the Holy Spirit”. Given that each major section in the book ends with some phrase like “and the word multiplied and spread”, it is perhaps most accurate to the “Acts of the Word” proclaimed by the Apostles under the leading and power of the Holy Spirit.
Again and again the apostles and Paul are depicted in extreme circumstances–in prison, under sentence of death, stoned by angry mobs. Always they were delivered, never for who they were but always for what they proclaimed. It was not the apostles who triumphed in Acts–it was the gospel that triumphed. Stephen is the prime example. He gave his life for that witness. But out of the tragedy of his death, the gospel triumphed–spread to Samaria, and all Judea, and ultimately to the ends of the earth. There is a triumphalism in Acts, but it is not a human triumphalism. It is a God-triumphalism, a triumph of his word in Christ. Nowhere is this clearer than in the shipwreck narrative. Paul was delivered, but he was delivered to bear witness. He was still a prisoner in chains when he bore his witness in Rome. The book closes with his bold, unrestricted proclamation in the capital city. The gospel had reached its ultimate destination as set forth in Jesus’ commission to the apostles (1:8). It had reached the “ends of the earth.” It had triumphed. But Paul remained under arrest. … Whatever may have been the outcome of Paul’s Roman imprisonment, Luke seems to have deliberately chosen to end his story where he did. He ended not on Paul but on the gospel, on the message of the kingdom. The word of God in Christ–not Peter, not Paul–is the real hero of Acts. (POLHILL, NAC)