Athanasios the Great was a prominent Christian theologian and bishop of Alexandria in the 4th century. He is best known for his strong opposition to the Arian heresy, which denied the divinity of Jesus Christ. Athanasios played a crucial role in the development of early Christian doctrine, particularly at the Council of Nicaea in 325 AD, where the Nicene Creed was established. Throughout his life, Athanasios faced multiple exiles due to his beliefs and conflicts with various emperors. He is recognized as a Doctor of the Church and is celebrated for his writings, including "On the Incarnation," which articulate the significance of Christ's divine nature and the salvation of humanity.