The Bible affirms Paul's apostleship as legitimate, primarily through his encounter with the risen Christ and the establishment of the Corinthian church.
In 1 Corinthians 9:1, Paul defends his apostleship by asking if he is not an apostle because he has seen the Lord Jesus Christ and has demonstrated this through the establishment of the church in Corinth. His authority and legitimacy as an apostle are confirmed by the work he has done in the Lord, showing that he was chosen by God to reach the Gentiles. Despite being 'one born out of due time,' Paul asserts that God used him in a powerful way for the sake of the Gospel. He contends that if he were a fraud, the very faith of the Corinthians would not exist, indicating that his apostleship is validated by their belief and conversion.
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