The oral word and preaching of the apostles preceded the written word, considering the best evidence showed that 30 years passed before the earliest epistles were written.
Jesus gave all authority to the apostles who in turn passed on their authority to their successors.
The apostles preached before the written word?
Isaiah, Kings, Genesis, etc are not the written word?
The oral word preached did not proceed the written as they only preached what had been from the beginning and was read every Sabbath. The apostles had no idea their letters would become Scripture so your statement is misleading at best
Jesus gave all authority to the apostles
Got a Scripture passage for that
Scripture?