Why were the saints at Jerusalem poor and in need of help?
The saints at Jerusalem had pooled all their resources since Pentecost, and their common treasury ran out, leaving them destitute. Their poverty came about because of their obedience to the Word of God, and God supplied their needs through the offerings of Gentile believers.
Les explains that the little churches founded in apostolic days probably met in homes and often did not have full-time pastors, yet Paul still gave instructions for gathering offerings. At that time, the offerings were primarily for the poor saints dwelling at Jerusalem. They had been pooling all their resources since Pentecost, and the common treasury ran out, leaving them destitute. Because they were destitute due to their obedience to the Word of God, God in turn took care of them through the offerings of Gentile believers. Paul stressed that the Jews were worthy of material gifts because of the spiritual things they had given to the Gentiles. Paul deals with giving for almost three chapters: 7, 8, and 9.