Exploring the Mystery of Incarnation: Insights from St. Thomas Aquinas

The Heart of Christian Faith: The Incarnation

The Christian doctrine of the Incarnation holds a central place in the faith, asserting that Jesus Christ embodies both true divinity and true humanity. This belief underscores the profound mystery and beauty of Christianity, where the eternal Son of God enters the temporal realm, assuming a complete human nature to bring about our salvation.

St. Thomas Aquinas, in the third part of his Summa Theologiae, delves deep into this doctrine, aiming to elucidate its coherence and deep intelligibility. Aquinas begins with divine revelation and the Church's apostolic tradition, ensuring his explanation aligns with the foundational teachings of Christianity, as affirmed by the early Church councils.

Early Misinterpretations of Jesus' Nature

The early Christian era was rife with controversies regarding Jesus' nature, leading to several heretical views:

• Docetism: Proposed that Jesus only seemed human and merely appeared to suffer, quickly dismissed by the Church as it contradicted the real human experiences of Jesus, including his suffering and resurrection.

• Adoptionism: Suggested that Jesus was a mere man adopted by God, a view rejected because it undermined the pre-existence of the Son of God who became incarnate through the Virgin Mary.

• Arianism: Claimed the Son of God was a created being, not truly divine, a notion denounced at the Council of Nicaea in 325 AD.

• Nestorianism: Attempted to separate the divine and human aspects of Jesus, a perspective condemned for failing to recognize the unity of Jesus' nature as both human and divine.

The Hypostatic Union Explained

The Council of Chalcedon in 451 AD provided a definitive statement, affirming Jesus Christ as one person in two natures — divine and human. This union, known as the hypostatic union, signifies that the divine person of the Son assumes a complete human nature without merging or altering either nature.

Aquinas offers a synthesis of this teaching, emphasizing several key points:

• The metaphysical foundation of the hypostatic union, where the divine person of the Word subsists in a complete human nature.

• The unchanged nature of the divinity and humanity in Christ, ensuring that Christ remains fully divine and fully human.

• The uniqueness of this union, which is neither accidental nor comparable to simple human experiences like wearing new clothes or undergoing an organ transplant.

The Instrumentality of Christ's Humanity

Aquinas draws an analogy between Christ's humanity and an instrument in the hand of a carpenter, where the humanity of Christ serves as an instrument conjoined in the person of the Son. This allows the divine Word to perform actions in the world, such as healing and teaching, which in His divine nature alone He could not.

This profound union between God and man in Christ not only redeems humanity but elevates it to an unimaginable dignity, offering a participation in divine life. Aquinas, following Pope St. Leo the Great, marvels at this