Last week we shared stories about how we began following Jesus. This week, briefly share a moment in your life that was particularly 'Spiritual', where you felt particularly close to God or even empowered by Him in some special way.
Read Jesus' final promise to his disciples:
Read Acts 1:1-9
What do you think the disciples were thinking/feeling here as they talked with the resurrected Jesus? 
What significant words did Jesus use to talk about the Holy Spirit in these final remarks?
Do any of these sound familiar to you (think back to the last six weeks of bible studies and sermons!)
How could Jesus' promise of the Holy Spirit be a surprising fulfilment of the disciple's expectations for the coming of God's Kingdom?
Read Acts 2:1-3
Pentecost was a Jewish festival celebrating two things:
1. The Spring harvest. People would bring in the 'first-fruits' of their fields as an offering to God;
2. The receiving of the Law at Mount Sinai, fifty days after the passover and the escape from Egypt.
What do you think was the significance of the Holy Spirit coming at this particular festival?
Why do you think the Spirit arrived in such a dramatic way? What does it mean that the Spirit came like a violent wind storm with tongues of fire?
Read Acts 2:4-21
The Holy Spirit empowered the apostles to speak in other languages, or 'tongues'. In this particular case, they were enabled to speak the languages of the people gathered there from all over the known world. In other cases, people are enabled by the Spirit to speak in a Spiritual language - but we are not examining that phenomenon here. 
How did the Spirit empower the apostles to begin the work Jesus had instructed them to do in Acts 1:1-9?
How did all these things serve as a fulfilment of Joel's prophesy (in vv17-21)?
How else can the Spirit empower God's people to build the Kingdom of God?
Do you have any stories from your own life about this?
Spend some time praying, inviting the Holy Spirit to empower you in various ways for the sake of God's Kingdom.
 They must, after all, have been very puzzled. Nothing that had happened in the previous few weeks had corresponded at all to their game plan. As far as they were concerned, when Jesus called them and taught them in Galilee during the previous three years or so, they were signing on for some kind of Jewish renewal movement. They believed that God had appointed Jesus to be the true King of Israel, even though most of their contemporaries were still (to say the least) suspicious of him. They had seen Jesus rather like King David in the Old Testament, who for several years was a kind of king-in-waiting, standing in the wings with a ragtag group of followers wondering when their turn would come. Jesus’ motley band of followers had imagined that he would be king in some quite ordinary sense, which was why some of them had asked if they could have the top jobs in his government. Jesus, with his extraordinary healing power and visionary teaching, would rule in Jerusalem, and would restore God’s people Israel...
All of this could be summed up in the phrase: ‘restore the kingdom to Israel’. That’s what they were hoping for, and the question was natural: ‘Are we nearly there yet?’
- N.T. Wright, Acts For Everyone (Part 1), pp7-8
 Tom Wright's explanation of the Gift of tongues (below) is a great introduction to the topic, if your group would like an introduction to the topic. However, I am aware that it can be a controversial topic to discuss, so don't get too sidetracked by it!
In many religious traditions, people who experience certain types of ecstasy have sometimes found themselves speaking, praying or even singing in what seem to them to be languages which they do not themselves understand. Sometimes these turn out to be actual languages which are understood by one or more listeners: this is what is described in Acts 2, and there are many examples from subsequent periods including our own. Sometimes they appear to be a kind of babbling semi-language corresponding to no known human tongue. Sometimes the speaker may be unable to decide which it is. Paul was well aware (1 Corinthians 12.1–3) that phenomena like this could occur in non-Christian contexts, but for him, and for millions since (not least in today’s Pentecostal and Charismatic movements, though much more widely as well), such prayer was and is powerful in evoking the presence of Jesus, celebrating the energy of the spirit, and interceding for people and situations, particularly when it isn’t clear what exactly to pray for (see, perhaps, Romans 8.26–27). There is however no good reason, within early Christian teaching, to suppose that ‘speaking in tongues’ is either a necessary or a sufficient sign that the holy spirit is at work in and through someone’s life, still less that they have attained, as has sometimes been claimed, a new and more elevated level of spirituality than those who have not received this gift. To be sure, in Acts 2, and also in Acts 8.17 (by implication at least), 11.46 and 19.6, ‘tongues’ is a sign that the spirit has been poured out on people who weren’t expected to be included in God’s people. But there are plenty of other times when the spirit is powerfully at work without any mention of ‘tongues’, and equally every indication (e.g. 1 Corinthians 12 and 14) that praying in tongues is, for some, a regular practice and not merely an initiatory sign.
- N.T. Wright, Acts For Everyone (Part 1), p211