The Book of Acts, as with the other books and letters included in Scripture, does not officially have a name. (However, it was certainly named very soon after it was written.) (Also, however, it’s possible that Mark 1:1 was written as a title to that particular book.)
(By the way, the name “Acts” itself comes from the Greek term praxis, which means “activities”, a word that only shows up in Acts 19:18, and not in relation to the activities of Jesus Christ, the Twelve, or other disciples.)
In most English Bibles (perhaps all?) the Book of Acts is called “The Acts of the Apostles.” However, there are at least two problems with that title.
First, consider the opening of the book in which Luke writes to Theolphilus:
In the first book, O Theophilus, I have dealt with all that Jesus began to do and teach, until the day when he was taken up, after he had given commands through the Holy Spirit to the apostles whom he had chosen. He presented himself alive to them after his suffering by many proofs, appearing to them during forty days and speaking about the kingdom of God. (Acts 1:1-3 ESV)
Luke tells Theophilus that his first book (i.e., the Gospel of Luke) dealt with “all that Jesus began to do and to teach.” It follows, then, that this particular books (Acts) would deal with “all that Jesus continued to do and to teach.” The Gospel of Luke, according to its author, contains the beginning of a story. Luke second book, Acts, would then contain the continuation of that story.
Now, it’s true that Acts 1:1-3 mentions the apostles. However, Luke does not say that the book will contain what the apostles did (i.e., praxis or “acts”). Instead, Luke records that Jesus gave commands to his apostles. We know that Jesus gave commands to other disciples also (not just the Twelve), because Luke records that in Acts 1:8, which was apparently spoken to at least 120 disciples. Luke also records Jesus appearing to and teaching many disciples (other than the Twelve) in Luke 24. So, the mention of “[giving] commands… to the apostles” in Acts 1:3 does not appear to be exhaustive.
So, perhaps a better title for the Book of Acts would be “The Acts of Jesus Christ.” However, even that title doesn’t cover everything.
Second, apart from the first few verses of the book, and a few verses in Chapter 9, Jesus does not directly appear in the Book of Acts. Yes, he is mentioned or is the subject of many, many, many sentences, paragraphs, sections, chapters, etc.
So, who were the main characters in the Book of Acts? Certainly, the twelve play a huge role in Acts. The early parts of the Book follows the activities of the Twelve very closely. However, we can’t say that Luke focuses only on the Twelve. In fact, from chapter 6 through chapter 9, the focus is not on the activity of the Twelve, but on the activities of other disciples.
Also, it’s clear that in the last half of the Book of Acts, Luke focuses on the apostolic (traveling) work of Paul and those who traveled with him (including Luke). Now, while I agree that Paul is an apostle, he is never included in the Twelve. Also, there are some within this section that are named as apostles, while others who are not called apostles serve as well.
If we take all of this together, we can see that Luke is demonstrating how Jesus Christ was working through many of his disciples. Yes, he worked through the Twelve. He also worked through other apostles. He worked through some gifted as prophets and evangelists. He worked through some whose giftings were not named.
Many of the activities carried out and persecutions faced by the Twelve in the early part of Acts are later carried out and faced by others in the book who are not part of the Twelve. So, Luke focuses on the activities of Jesus Christ that he carries out through various disciples.
Thus, perhaps a better name of the Book of Acts (instead of “Acts of the Apostles”) would be “The Acts of Jesus Christ through his Disciples.”
What do you think? Can you think of another name that describes Luke’s second book to Theophilus?