Yesterday we noted the centrality of the city of Jerusalem for Luke-Acts. Here is a quote which notes the centrality of the church in Jerusalem.
"That the Jerusalem church held a uniquely important and authoritative place in earliest Christianity is also plainly evidenced in Acts. The earliest circle of believers is ordered by the resurrected Jesus to remain in Jerusalem (1:4), where the first Christian proclamation occurs (chaps. 2-7). As in Gal 2:1-10, it is to Jerusalem that a delegation from the church of Antioch goes for a definitive ruling on the question of Gentile admission. Similarly, it is to James and the elders of the Jerusalem church that Paul presents himself in Acts 21. This list could be extended considerably, but the point should be obvious: in Acts, Christianity begins and remains centered in Jerusalem."
Craig C. Hill, "the Jerusalem Church," in Jewish Christianity Reconsidered: Rethinking Ancient Groups and Texts, ed. Matt Jackson-McCabe (Minneapolis: Fortress, 2007), 45.