How did the early apostolic churches grow without the written Word?
The early apostolic churches grew without the written Word by depending on gifted men whom God enabled to proclaim and teach the Pauline doctrines orally. These gifted teachers could speak forth God's Word without any printed New Testament, since the Gospels and Paul's letters had not yet been written or circulated as Scripture. Their growth came through that God-given proclamation.
Les explains that when Paul wrote to the Corinthians, no New Testament had yet been written. The Gospels had not been written, and Paul's own letters had not yet gone out as the Word of God. These early, primitive, apostolic churches were experiencing growth and reaching out in the pagan world without the benefit of the written Word. Therefore they had to depend on gifted men, who could teach people the Pauline doctrines and proclaim the truth of God's Word without having it in print. Paul, by inspiration, recognized that this gift was the most important thing the local church could have. Later, as he said in chapter 13, that gift would fade away because the printed page would be available, so they would no longer need men gifted to proclaim the Word without anything to go on.