First, Saint John of Capistrano was a lawyer, and then he was governor of Perugia, a city in Naples, Italy. He later became a Franciscan priest. Father John was a marvelous preacher, and he traveled all through Europe to teach people the importance of penance and to start new religious communities. In 1456, when Father John was 70 years old, the Ottoman Empire was threatening to take over Vienna and Rome. Pope Callistus III asked John to lead a crusade of 70,000 Christians. The Holy Father instructed all other Christians to pray for the defenders, and he had all churches ring their bells at noon as a reminder. Father John and his crusaders were successful.
To this day, Catholic churches all over the world ring their bells at noon as a call to prayer. Today at noon, ring bells in your home, and then pray the traditional noon prayer for Catholics, the Angelus.