When the two Lukan books are considered as a unit, the combined work reveals a unified purpose and structure. Most scholars believe that Luke wrote his works for a church composed of Greek-speaking, mainly Gentile, converts to Christianity. Luke sought to explain Christ in terms that would make sense to his particular audience. Many of the Jewish features of the earlier gospels, particularly of Matthew, are dropped by Luke. So, for example, Luke drops the use of most Hebrew or Aramaic words. Likewise, where Matthew in accordance with Jewish sensibility uses paraphrase to avoid the word ‘God’, Luke uses ‘God’: Matthew, ‘kingdom of heaven’; Luke, ‘kingdom of God’. Luke shows particular interest in the interactions of Jesus with Gentiles. Where Matthew takes the genealogy of Jesus back to David and Abraham (Matthew 1:1, 2, & 6), who are particularly significant for Jews, Luke takes the genealogy back to Adam, the universal Biblical ancestor (Luke 3:38). In short, Luke endeavors to present Jesus in a manner relevant to a general, Gentile audience, and has less concern than Matthew with the narrower task of explaining Jesus to Jewish converts. Luke and Acts show Christianity breaking out of its original Jewish matrix into the wider world.
This universalist goal in Luke/Acts also is the end point of the combined work. Human history, under God’s Providence, begins in Luke 3 with ‘Adam, the son of God’, the forefather of all humanity. The history of Luke-Acts ends with the arrival of the apostolic mission at the center of the Roman empire in Acts 28:14-31, in a kind of fulfilment of Christ’s commandment in Acts 1:8. In between this universal beginning and ending, Luke’s gospel ends and Acts begins with a common, central point, namely with the glorified Jesus in Jerusalem. In Luke all of human history narrows down to the risen and glorified Lord in Jerusalem. Acts begins with this same glorified Lord’s ascension, then moves the story outward again to the whole human world. The power behind this spread is the Holy Spirit, bestowed at Pentecost in Acts 2. While Pentecost itself is a Jewish affair, in 2:5-11 it anticipates the universal spread of the Church at its starting point by the great geographical diversity of the (Jewish) witnesses to the Pentecostal manifestations. The Church will spread beginning with Jews in Palestine, then to Jewish communities in the wider world, and then to Gentiles everywhere.
With these comments in mind, we may outline the combined work of Luke-Acts and its joint vision of sacred history, as follows:
A/Luke – Common origin of all in Adam, the son of God
B/Luke – History of humanity and Israel leading to Jesus
C/Luke – Ministry of Jesus among the Jews and Samaritans
D/Luke/Acts – Resurrection-Ascension-Pentecost in Jerusalem
C/Acts – Ministry of Apostles in Judea and Samaria
B/Acts – History of Jewish and Gentile converts from Jesus (Church mission)
A/Acts – The Church comes to Rome
Once the structure of Luke-Acts as a whole is understood, it is easy to see Acts in particular outlined in a single early verse, namely Acts 1:8. This verse briefly summarizes the rest of the book. The apostles after the Ascension will be endued with power by the Holy Spirit in Jerusalem, in order to begin the expansion of the Church through conversions in Jerusalem, the rest of Judea and Samaria, and then to the end of the earth. This mission (C/Acts, B/Acts, and A/Acts) fulfils the divine command of 1:8, but also completes the united outline with Luke. The Spirit-guided fulfilment of the mission given by the risen Lord brings to all of Adam’s children the new life that flows from the cross and resurrection of Jesus. The fullness of the Church and her mission (B/Acts, by way of anticipation at least), balances the melancholy history of fallen humanity and fills the time between Christ’s ascension and his second coming. Furthermore, the coming of the Church to Rome with Paul in chapter 28 opens the history of the early Church in Acts into the wider history of the Church after the New Testament period. Paul’s preaching in Rome is only the symbolic, not the actual, bringing of the gospel to the ends of the earth. It remains for subsequent generations – the readers of Acts inspired by the stories of Peter and James and John and Philip and Barnabas and Paul – to complete the work.
On the basis of this understanding of Acts 1:8, the book may be outlined in terms of the fulfilment of 1:8: ‘But you shall receive power when the Holy Spirit has come upon you, and you shall be my witnesses in Jerusalem and in all Judea and in Samaria and to the end of the earth.’
The Holy Spirit comes upon ‘you’, that is the apostles (1:13) in Jerusalem (1:12) on Pentecost (2:1).
Thereafter the apostles, primarily Peter, preach to and increase the Church in Jerusalem (chapters 2-5), where Stephen also preaches and is martyred (chapters 6-7).
The martyrdom of Stephen and persecution of Christians in Jerusalem (8:1) introduces Saul and leads to a scattering of Christians (8:4) throughout Judea and Samaria (8:1). The ministry of Philip, confirmed by the apostles, is particularly in Samaria (8:4-25).
The spread of the church ‘to the end of the earth’ then occurs in multiple ways, beginning with Philip’s preaching to and baptism of the Ethiopian eunuch (8:26-40) and the conversion of Saul and his work in Antioch (chapter 9:1-30). 9:31 renews the outline to that point in the book with mention of Jerusalem, Judea, and Samaria, and it asserts that the Church, now built up in these places, is Spirit-filled and at peace.
The renewal of the outline in 1:8 in 9:31 proves transitional, as it leads to the final stage of the outline: with 9:32 the Gentile mission begins in earnest. Peter converts a Gentile in Judea (9:32) under direct, divine command. Thereafter the mission to the ‘end of the earth’ flows forth with missionary journeys, especially involving Paul and his associates. Throughout the story of the expanding missions there are periodic references to the central Church in Jerusalem and periodic Pentecost-like moments and periodic assertions of the presence of the Spirit. The Church is growing beyond its Jewish matrix, but without any fundamental rupture or discontinuity in its message (the apostolic witness to the risen Lord) or inspiration (the Holy Spirit). In fact, the Gentile mission is implicit in the initial command (1:8) as well as in the ministry of Jesus himself as recounted in Luke. The conclusion of the account in Acts of Paul’s missionary journeys comes with his arrival in Rome, which was the capital of the great empire of the age. This arrival and Paul’s preaching in Rome fulfil the outline of 1:8.
The openness of Acts to subsequent Church history serves another purpose noted by many scholars. That is, by the likely date of Acts in AD 80-90, Christians had begun to sense that the return of Jesus was quite possibly not imminent. The ‘delayed Parousia’, or Second Coming, of the Lord left Christians with a task beyond passive fidelity and mere endurance during a brief period of waiting. There is an age of unknown and unknowable length between the first and second comings, and that age is the age of the Church and her active mission. The idea of sacred history present in Luke and Acts provides for the delayed Parousia.
Some scholars believe that Luke papers over many conflicts and gives an unrealistically optimistic picture of unanimity and success. But in fact Acts does not suppress stories of persecution from without or of conflicts within. Many arrests and interrogations are described, and the martyrdoms of Stephen and James are noted. Quarrels over doctrine, as between those who favor Judaizing and those who do not, and over clashing personalities and mission strategies are frankly presented. What Acts does show is that the Church found ways to resolve or isolate such conflicts so as both to survive and also to expand. In general the story is one of steady guidance by the Holy Spirit and of steady growth both in numbers and in geographical extent. Perhaps the resolution of difficulties was more complex than described. It is sufficient for Christians to believe that the basic outline of events provided in Acts is accurate, not that it is exhaustive and comprehensive.
Insofar as secular history deals with the same material as Acts, the book indeed seems to present information fairly accurately. The accounts of events in Acts can be compared on occasion with versions of events in the gospels, in Paul’s letters, and with secular historians. Sometimes there are conflicts or tensions between accounts, particularly concerning the timing of the ascension and Paul’s relations with the Jerusalem apostles. Within Acts some events, such as the conversion of Paul and Peter’s conversion of Cornelius, are told more than once, which allows for internal comparisons. We will discuss such cases in detail when they arise below. Acts certainly has a perspective, and it certainly interprets events through the lens of that perspective. Nonetheless, Acts is historical writing of a sort familiar to the educated contemporaries of its author.