According to the Bible, in the book of Acts, Herod persecuted the early church because he was opposed to the Apostle's teaching. Herod saw that the Apostles were gaining many converts to Christianity and he felt threatened by their message. He arrested and killed James, the brother of John, and when he saw that this pleased the Jewish leaders, he arrested Peter as well. Herod was trying to suppress the spread of Christianity and maintain his own power and authority. Therefore, it was his opposition to the Apostle's teaching that motivated him to persecute the early church.