Why did the early believers in Acts 2 gather in their own little fellowship groups?
Because they had separated from the mainstream of Judaism, their own little fellowship groups became the only place they could really talk together. There they devoted themselves to the Apostle’s Doctrine, fellowship, breaking of bread, and prayer, and they shared meals together in homes.
Les explains that in Acts 2 the believers were contending in the Apostle’s Doctrine, which did not yet include the later revelations given to Paul. He emphasizes that Scripture is a progressive revelation: God does not unload everything at once but reveals truth as He sees fit. Because these believers were separated from the mainstream of Judaism, the only place they could talk together was in their own little groups of fellowship. They had meals together, and Les often illustrates that casual acquaintance becomes real fellowship when someone invites you into their home for a meal.