1. The Unfinished Story...
The book of Acts is the second part of Luke's work (v.1). Both go together and each is incomplete without the other. In terms of the NT, they are very significant and account for 26% of the total.
But why is he writing? Back in Lk. 1:1-4 he told Theophilus it was so that "you may know the certainty of the things you have been taught". This second volume continues that work by focussing on what Jesus continues to do after his death and resurrection: the gospel of Luke was about what Jesus "began to do and to teach", the implication being that this second part will carry the story on.
But what is the story about? Luke's great theme is God's plan of salvation for his world, a plan foretold in the OT and, in the events Luke is writing about, now coming to fulfilment. He tells us here that the subject on which Jesus spoke to his disciples after his death and resurrection was "the kingdom of God" (v.3).
That reign has come to pass in the death and resurrection of Jesus. Here Luke stresses the resurrection, saying that Jesus gave his disciples during these 40 days "many convincing proofs that he was alive". The resurrection was certain and forms the ground of all that is to follow.
But those events do not stand alone. There is more to be done in terms of the saving reign of God. Jesus is returning to heaven but there is more to follow. That is hinted at in these opening verses where we read that Jesus gave "instructions through the Holy Spirit to the apostles he had chosen".
Those who had been with him would have a part to play and the Holy Spirit is going to be significant in the outworking of that role. The rest of this opening passage takes us into the roles of the apostles and the Spirit and the situation they will be facing.
2. The roles of the Apostles and the Spirit
So what is it that Jesus wants his apostles to do? Initially, nothing; they were to wait in Jerusalem until they received the gift the Father had promised them.
Before we look at that gift, notice here the note of fulfilment: God the Father has promised something, in the OT, and this is now the time for his promise to come to pass. These are momentous times!
Jesus says that the Father's gift to them is going to be the Holy Spirit himself. They will be baptised with the Spirit in just a few days time. John baptised with water, a baptism of repentance but this is going to be something far greater. They will be incorporated into God's family in the deepest possible sense, with God himself coming upon them and dwelling within them.
This raises a question in the minds of the disciples. They associated the coming of the Spirit with God's promise to restore his people (as the OT suggested) and ask Jesus if that is to be now (v.6). His answer forms, in a sense, the whole theme of this book of Acts.
First he tells them they're not going to be privy to God's schedule. That isn't to be their concern. And it isn't to be our concern either. The church has not been commissioned to spent it's time speculating about how and when God will act or when Jesus will return. Nothing could be clearer than that!
What will impact them is the coming of the Spirit. This great event will change everything and will be the defining moment in the life not just of these apostles but the whole church for the whole of time.
Jesus says 3 things about their role, the Spirit's role and the scope of their work.
i) They will be his witnesses - they were to be living examples of the reality of the kingdom, of the saving reign of God. But they had a particular function to fulfil. They were eyewitnesses of great events and were to bear witness to them. They had been with Jesus, they had seen the miracles and heard the teaching; they had witnessed his death and had known for sure that he had risen from the dead.
Everything that was to follow in terms of their ministry was to flow from this foundation point.
We cannot be witnesses in the same way today but the whole life and ministry of the church is to be built on this foundation. As we too live under the saving reign of God, we can proclaim hope to the world and call for repentance and faith precisely because these things really took place all those years ago.
ii) In the power of the Spirit - But no group of men, however much they have seen and heard, are going to be equipped for such a task in their own strength. We are talking about God's action to rescue men and women from sin, to push back the kingdom of darkness and to blaze his glory in this world.
Such a task would be unthinkable for unaided humanity. But Jesus here promises that such help as we need will be given: "You will receive power when the Holy Spirit comes upon you". Notice that he is given not primarily for the sake of the church but for the sake of the church's task. Of course, it is the most marvellous blessing to have God's Spirit dwell in us but here the emphasis is clearly on what he empowers us to do.
iii) Not only do the apostles need to know that the Spirit will empower them for the task, they need to know the scope of that task. They were thinking still in terms of national Israel but Jesus corrects them and tells them here that their task of being witnesses to this saving plan of God is to extend throughout the whole world: "in Jerusalem, and in all Judea and Samaria and to the ends of the world".
The task of the church today remains the same. The gospel is for all people, of all nations. Mission is about the gospel at home and abroad. We need to have a large vision that takes up this great commission.
3. Closure
Having laid out the task and the means for it, this opening passage closes with an account of the ascension of Jesus. This isn't something incidental but follows on precisely from what Jesus has just been saying.
There are parallels here with the story of Elijah going up to heaven in the OT and Elisha being commissioned to carry on his work. This is no mere prophet, this is the Messiah himself yet his work is being entrusted to the men who have been with him and they will know his Spirit coming upon them.
The ascension of Jesus also brings about a sense of closure in the story. They are to be witnesses of what they have seen and heard. They are not going to be witnesses to new things but to what has happened. Jesus has ascended to the highest place, he is now seated in power; their task, our task, is to proclaim him as the exalted King and only Saviour of mankind.
But we need to listen to the words of the angels in this scene. The apostles stood gazing up into the sky but God's word to them through his angels was not to do that. Jesus has gone and will return one day; they now need to live and minister in the time in-between. Yes, one day the kingdom will be fully realised, when Jesus returns. But until then, there is work to be done.
John Stott's comments on this are very challenging and form an appropriate conclusion:
There was something fundamentally anomalous about their gazing up into the sky when they had been commissioned to go to the ends of the earth. It was not the sky which was to be their preoccupation. Their calling was to be witnesses not stargazers. The vision they were to cultivate was not upwards in nostalgia to the heaven which had received Jesus, but outwards in compassion to a lost world which needed him. It is the same for us. Curiosity about heaven and its occupants, speculation about prophecy and its fulfilment, an obsession with 'times and seasons' - these are aberrations which distract us from our God-given mission. Christ will come personally, visibly, gloriously. Of that we have been assured. Other details can wait. Meanwhile, we have work to do in the power of the Spirit.