The Incarnation and Two Natures
As taught in the Reformed / Presbyterian tradition
Defining the union of the divine and human natures in the one person of Jesus Christ without confusion or change.
In the Reformed tradition, the doctrine of the Incarnation is not merely a Christmas sentiment but the central hinge of the history of redemption. The question this subtopic answers is fundamental: How can a holy and infinite God reconcile to Himself a sinful and finite humanity without compromising His justice or the integrity of His being? The Reformed answer lies in the person of the Mediator, the Lord Jesus Christ, who is eternally the Son of God and became, in the fullness of time, truly man. This mystery—often called the Hypostatic Union—posits that two distinct natures, divine and human, are joined in one person forever, without mixture, change, division, or separation.
By the end of this lesson
- **Identify** the biblical and historical foundations of the Hypostatic Union, specifically the "four adverbs" of Chalcedon.
- **Distinguish** between the "communication of properties" (*communicatio idiomatum*) as understood in the Reformed tradition versus the Lutheran and Roman Catholic traditions.
- **Explain** the theological significance of the *extra calvinisticum* and why it is essential for preserving the divine transcendence in Reformed Christology.
- **Articulate** the necessity of Christ’s full humanity and full divinity for the accomplishment of a perfect atonement and the office of High Priest.
- **Trace** the development of the "Two Natures" doctrine through the Scripture anchors of John 1, Philippians 2, and Hebrews 2.
- **Defend** the doctrine of the Incarnation against ancient and modern heresies such as Arianism, Docetism, Nestorianism, and Eutychianism.
- **Apply** the comfort of Christ’s sympathetic humanity to the daily life of the believer, particularly in prayer and suffering.
- **Compare** the Reformed emphasis on Christ’s "Active Obedience" with the necessity of His incarnate state.
Scripture
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