Acts

Chapter one explains Luke's purpose in writing. It was to follow up all that Jesus began to do and teach with the sending of the Holy Spirit to empower the disciples as his witnesses from Jerusalem to the ends of the world.  

The church is born when many in Jerusalem for the Feast of Weeks repent and are born anew by the Holy Spirit.  

There is one last chance for Israel. This chapter describes God's final offer. 

Jesus earlier told his disciples in a parable that the leaders of the jews and the nation would have another year or two before their fate  was sealed. In this chapter they have reached the end of that time and have not repented.  

God was serious about the church and their testimony about Jesus the Lord. If sin muddied that testimony, if needed to be called out.  

New needs drove the organization of the church. Specifically, the need to fairly serve the growing diversity of the church reslted in  the institution of Deacons.