How do we know the doctrine of Christ's two natures is true?

The doctrine of the two natures of Christ—the divine and the human—holds a central place in historic Reformed theology. John 10:30 states, 'I and my Father are one,' which affirms Christ's divinity. Furthermore, the human nature of Christ, described in Scripture as a 'Holy Thing' (Luke 1:35) and a body prepared for Him (Hebrews 10:5), underscores His full humanity. This duality is critical because it allows for a genuine atonement; only a Savior who is both God and man can mediate between God and humanity.

By understanding that Christ’s human nature does not exist apart from His divine nature but instead is in a mysterious union, we affirm the necessary obedience and suffering of Christ. As Philpot argues, to dismiss the concept of 'the blood of God' is to undermine a fundamental truth of salvation. The Scriptures clearly teach that it is through this union that Christ accomplishes redemption, making the doctrine central and irrefutable for faith.