What did the Holy Spirit falling on the Gentiles prove to the Jewish believers who were present?
The Spirit's descent signified to the seven Jewish believers present with Peter that these Gentiles had become believers. It evidenced their salvation by faith, faith alone, even before repentance or baptism, and before Paul's gospel, showing they believed only that Jesus was the Christ.
Les explains that Peter and six other Jewish believers went to the Gentile home of the Roman officer Cornelius. While Peter had not even finished preaching, and had not yet said anything about repenting or being baptized, the Holy Spirit came down. This signified to those seven Jews that these Gentiles had become believers. They were evidencing salvation by faith, and faith alone, not yet Paul's gospel, only that Jesus was the Christ. It happened without an invitation, without walking an aisle, without repenting, and without baptizing.
And they of the circumcision which believed were astonished, as many as came with Peter, because that on the Gentiles also was poured out the gift of the Holy Ghost.
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