“Paul asked questions like ‘Have you received the Holy Ghost since you believed? Read Acts 19.” Doesn’t this show that Paul believed that Acts 2:38 was the New Birth?
This does not prove that Paul taught or practiced Acts 2:38 as the UPCI believes it.
A closer look shows that the situation in Acts 19 is not so simply explained. When Paul visited the men in Ephesus, he tested whether they had heard about Christ by asking them if the Holy Spirit had come to them. It was the Holy Spirit that always opened hearts to believe the Gospel (cp. Caesarea, Lydia, et. al.). It was the Holy Spirit that came on those who believed the Gospel. If they knew about the Holy Spirit, then they would necessarily know about Jesus and the Gospel. When they said they had not heard about the Holy Spirit, Paul knew that they were not believers in the Gospel. At that precise point, Paul preached the Gospel to the Ephesians by explaining to them that they should “believe in Him who was coming after him, that is, in Jesus.” (Acts 19:4 NAS). This is what Paul told them to do. He did not tell them they would not be saved unless they were baptized. He did not teach them that the real secret was to be baptized with the formula “in the name of Jesus” only. He did not tell them they needed to prove they had the Holy Spirit by speaking with tongues. None of that was necessary because Paul did not believe or teach those ideas. He told them they needed to believe in Jesus – the one that John, their leader, preached about.
Later when Paul spoke his final words to the elders of the Ephesian churches, he reconfirmed the priority of the Gospel to them by restating his mission: “that I may finish my course, and the ministry which I received from the Lord Jesus, to testify solemnly of the gospel of the grace of God.” (Acts 20:24 NAS). Paul could have told them, “Keep preaching baptism in Jesus name.” or, “Don’t ever let go of speaking with tongues as the initial evidence.” But he never even hinted at those notions. He reminded them that the center of his ministry – the ministry by which God brought them into the Church – was the “gospel of the grace of God.”
To best understand how Paul truly understood the events of Acts 19 we need only to read his words in Ephesians 1:13 (NAS): “In Him, you also, after listening to the message of truth, the gospel of your salvation-- having also believed, you were sealed in Him with the Holy Spirit of promise,” The sequence of events as Paul states them is simple. The Ephesians heard the “gospel of your salvation” and then believed. When they believed they were “sealed in Him [Christ] with the Holy Spirit.” The Holy Spirit opened their hearts to believe the Gospel, and then he sealed them into Christ. There were not sealed because they spoke with tongues. They were sealed with the Holy Spirit when the believed the Gospel.
The picture of what happened in Ephesus is very evident when you read all the Ephesians texts together in their proper historical order: First, Paul preached to them to “believe . . . in Jesus.” Next, Paul exhorted the Ephesians about the centrality of the “gospel of the grace of God.” Finally, Paul reminded them in an epistle that they had received the Holy Spirit at the time they believed the Gospel. There is no mention of a specific form of water baptism or of any necessary evidence such as speaking with tongue. There is not even a hint of these doctrines. But, the idea of believing the Gospel – faith alone in Christ alone – is central and conspicuous to Paul teaching about salvation.
