How do we know that Christ was sinless?

The sinlessness of Christ is a foundational doctrine for Christians, affirmed throughout Scripture. He is described in 1 Peter 1:19 as a lamb without blemish or spot, highlighting His perfect obedience and purity. This sinlessness was necessary for Him to serve as our representative and substitute, bearing the sins of His people by having our sin imputed to Him, as noted in 2 Corinthians 5:21. Thus, His complete lack of sin is integral to the nature of our salvation, providing the righteousness required for justification.