When God pours out the Spirit in Acts 2, hearers recognize some of the languages in which Jesus’s followers are (presumably rather loudly) praising God.
In Acts 2:16-21, Peter begins to explain this marvelous event in light of God’s earlier promises. He quotes from Joel 2:28-32, while also paraphrasing as needed (as was the custom) to highlight key points. In context, Joel announces the restoration of God’s people; Peter thus adjusts Joel’s “afterward” to “in the last days.” If Luke regards this occasion as already part of the “last days,” he must also view all subsequent events as “last days” as well.
For Luke, then, the future has invaded history: God’s promised restoration has already begun to dawn; “the kingdom of God has come to you” (Luke 11:20). Other early Christians spoke of the Spirit as the first fruits or first installment of our future inheritance (Rom. 8:23; 2 Cor. 1:22; 5:5). The Spirit provides a foretaste of the future age, when God makes everything new (1 Cor. 2:9-10; cf. 2 Cor. 5:17). Because we have tasted the life of the future, nothing in the present can ever be the same for us again. As citizens of a new age, we must work, like Jesus, to bring divine wholeness into the brokenness of the present age.
Because Joel speaks of prophesying, visions and dreams, Peter understands that the promise is also about prophetic empowerment. Even more frequently than in earlier Scripture, early Judaism often associated the Spirit with prophecy, but to make sure that no one misses the point, Peter adds in another line (the final line of Acts 2:18): “and they shall prophesy.” The Spirit empowers God’s servants to speak for God just as did the prophets of old. A wise preacher or witness may well tremble at the awesome task of speaking God’s message; but our confidence can be in God’s ability to touch hearts rather than in ourselves.
In the writings of the biblical prophets, the promise of the Spirit was for the time of the end, the time of Israel’s restoration (note in context Isa 11:2; 32:15; 59:21; 61:1; Ezek 11:19; 36:27; 37:14; 39:29; Joel 2:28-29). That is why the disciples suspected that God would even restore the kingdom immediately (Acts 1:6-8).
The Spirit brings into our lives a foretaste of the future age, so we can work for God’s kingdom here and now. If this broken world cannot see in the church at least a foretaste of God’s promised restoration, we have settled for too little. Let us, like the first disciples (Acts 1:14), pray for God to empower, transform, and renew us by his Spirit (Luke 11:13).