Were Paul's letters already circulating as Scripture in the early church?
No, Paul's letters were not yet circulating as Scripture in the early church. At that time, only the Old Testament was recognized as Scripture; nothing of the New Testament had been written, not even the Gospels. Paul's letters, even as they were being written, had not yet been circulated as the Bible.
Les explains that when Apollos came to Ephesus, the early church had only the Old Testament as Scripture. Nothing of the New Testament had been written yet, not even the Gospels. Paul's letters, even as they were being written, had not yet been circulated as the Bible. Therefore, the only Scriptures these people could preach from was the Old Testament. Apollos was eloquent and mighty in the Scriptures, but he knew only the baptism of John, and the Gospel of the Kingdom preached by Jesus and the Twelve was still basically Jewish, connected with Temple worship.