Paul preached the gospel, which is the power of God unto salvation to everyone who believes. He didn’t first establish that there was a hierarchy that alone could interpret the Scriptures. When you preach to Hindus, does not the Holy Spirit take the Word of God and convict them and bring them to Christ? The Holy Spirit bears witness even in the hearts of unsaved that this is the truth of God! That is all we need—not some magisterium!
"And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither."