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

The doctrine of Christ's impeccability, meaning that He could not sin, is rooted in His divine nature as the Son of God. In John 14:30, Jesus articulates, 'the prince of this world comes and has nothing in me,' indicating that Satan found no claim or foothold in Him. Theologically, this speaks to the idea that since Christ is God, He is inherently incapable of sinning. His dual nature, being fully God and fully man, does not compromise His holiness; rather, it affirms it (Colossians 2:9). Furthermore, the necessity of His impeccability aligns with the requirement for a perfect sacrifice in the propitiation of our sins. The sinless nature of Christ is comprehensive to the gospel, assuring believers of the complete efficacy of His atonement.