After Jesus was resurrected and returned to heaven, Peter and the other Apostles preached in many places, but only to Jewish people.
Cornelius was an officer in the Roman army. He believed in God, but he was not Jewish. An angel appeared to him and told him to send for Peter. Cornelius sent his men to find Peter, and the Holy Ghost told Peter to go with them.
At Cornelius’s house, Peter taught the many people who had gathered there. He told them about the gospel of Jesus Christ, and they felt the Holy Ghost and knew it was true. When Peter’s friends found out that he had preached to people who weren’t Jewish, they were shocked. But Peter told them he had learned that the gospel of Jesus Christ is for everyone. (See Acts 10:1–48; 11:1–18.)