The book of Acts, or the “Acts of the Apostles” as it is called, is the rest of the story which Luke wrote down for Theophilus (Luke 1:3; Acts 1:1). He initially “dealt with all that Jesus began to do and teach” (Acts 1:1). So we are given by Luke the continuation of that work. What was the subject of what Jesus began to “do and teach”? As Mark writes, Jesus began to teach the gospel and the Kingdom of God. He came preaching and teaching the message of the gospel. He came calling sinners to repentance and faith in Him. Jesus performed all the miracles that were foretold. He did all that was prophesied concerning the Messiah so that it is clear that Jesus is the Christ, the Son of God. The “gospel” as we refer to the birth, life, death, and resurrection of Jesus has been recorded by four different authors. Luke, one of those authors, wrote a very detailed and thoroughly researched account of this gospel. He wrote for a Gentile official who had converted to Christianity. The aim of Dr. Luke’s writing was to ground his excellency in the faith or in the truth. He wanted not only Theophilus to know the truth but to walk in it and stand firm in the faith and in the grace of God. The gospel was written so that we would believe it and embrace it and proclaim it also. But Luke isn’t finished with the story of Jesus and His Kingdom.
The gospel is the power of God unto salvation (Rom. 1:17) but the Spirit is the power behind the spread and effect of the gospel (Rom. 15:13, 19; 1 Cor. 2:4). And yet God also uses means such as His servants opening their mouths and going in His name with His mission and authority. Jesus’ final instruction to his disciples was to wait upon the “promise of the Father”, which was the Holy Spirit. They were to stay and wait for this “power from on high” that came from the Holy Spirit (Luke 24:49). But what was this power for? It was for the task or mission Jesus gave his apostles to go and “make disciples of all nations…” through baptizing and teaching (Mt. 28:18-20). Jesus ensured their success by his authority, instructed them in their assignment, and comforted them with his assurance. Then we find that Jesus’ very last act upon earth, as he ascended up to the heavens in the cloud, was to lift up his hands and bless his disciples (Luke 24:50), which led the disciples to worship and bless the Lord (Lk. 24:51). So, the apostles had been given authority from Christ, instructed in their assignment by Christ, encouraged by the assurance of Christ, and comforted with the approval of Christ. He has commissioned, instructed, assured, and blessed his apostles for their mission to continue the work He began.
“Then the seventh angel blew his trumpet, and there were loud voices in heaven, saying, “The kingdom of the world has become the kingdom of our Lord and of his Christ, and he shall reign forever and ever.”(Revelation 11:15)
Pastor John MacArthur gives a clear and fitting summary to the book of Acts:
“The gospel is preached, sinners are saved, the church is established, leaders are chosen, saints are edified, witnesses given for Christ, and all along, the believers are suffering for their noble effort and being rejected by the world, but the Lord is protecting them so that the gospel can be preached, and the elect will be gathered, and this is the history of the church until he returns.” (John MacArthur)
Luke is writing down this history so that followers of Christ might be firmly rooted and grounded in the grace of God. This is a history of the power of God unto salvation and the continuing ministry of Jesus in the spreading of the gospel and building of His Church throughout the whole world. Acts is the description of the Father’s answer to the Son regarding the “nations” and the “ends of the earth” as his inheritance (Ps. 2:8). Jesus asked and the book of Acts is a record of the Father keeping his promise. The book of Acts is also the outworking of the promise of Jesus who declared, “I will build my church, and the gates of hell will not prevail against it” (Mt. 16:18). Perhaps Dennis Johnson says sums it up best regarding the purpose of the book of Acts and its ongoing significance in our lives today:
“Like all Scripture, its purpose is to inform and deepen our faith in Jesus Christ. Acts does this in a special way, by letting us view how Jesus kept his promise to be with his church and build his church through the personal presence and power of the Holy Spirit. We watch as the risen Lord uses apostles and prophets to lay the foundation of the church in its new covenant form (its ‘last days’ phase, as Peter affirmed, Acts 2:17); and we discover the contours and priorities that must shape the church in our time as well. In some ways, the foundational period was unique. Not every age has apostles who having walked with Jesus before his death now give eyewitness testimony to his resurrection. But the foundation determines the shape of that edifice that is still, today, being raised up to the glory of God.”