Not everyone who heard the gospel in the first century was converted. In Acts 26, Paul makes a direct appeal to King Agrippa who would have been knowledgeable about the Old Testament scriptures and prophecies. During his days of persecuting the church, Paul would have sided with Agrippa and his forefathers (Herod the Great and the Herods who had killed John the Baptist and the apostle James). Paul explained why he stopped arresting and killing Christians and became one himself, concluding with asking Agrippa if he believes the prophets. Yet even though Paul KNEW that Agrippa believed, his belief did not save him because he refused to be converted. Let the non-conversion of King Agrippa serve as a reminder that mere belief is not enough to save–one must act on that faith and be converted!
Speak where the Bible speaks.