Saint Apollonius was a Christian martyr and is venerated in the Catholic Church. He is believed to have lived during the 2nd century and is known for his steadfast faith in the face of persecution. His story is often associated with the early struggles of Christians in the Roman Empire. His feast day is celebrated on January 17, and he is often depicted in art holding a book or scroll, symbolizing his commitment to spreading the teachings of Christianity. Saint Apollonius is recognized for his role in defending the faith and is remembered as a symbol of courage and conviction.