 Many Jewish people got wind of this, that Christ promised to come back, and they moved to Jerusalem anticipating that this would soon happen. This put a real strain on the economy of those Jewish believers. Secondly, because of personal sacrifice. All believers in Jerusalem were actually sacrificing all of their things for God and for one another. They were selling things and distributing things to the poor because they actually believed that Christ was going to come back very soon and establish his kingdom right from the very mount from which he ascended.