Luke sets a lavishly detailed stage for the events that take place in Acts 2. At the conclusion of his gospel, Luke preserves Jesus' instructions to the disciples that they wait in Jerusalem until they "have been clothed with power from on high" (Luke 24:49). This mandate is then repeated in his introductory section to the book of Acts. Jesus specifically promises the baptism of the Holy Spirit to his disciples as well as an accompanying gift of power (Acts 1:4-8). The purpose of this gift is also made clear: It is to be used by the disciples so that they may be "witnesses" for Christ throughout the world.

Although Luke records the re-establishment of the apostolate by the election of Matthias to the twelve, it is clear that the disciples are still waiting around for some sign which will g…