How do we know Jesus can save us from sin?

The certainty of Jesus' ability to save from sin stems from His identity as the sinless Son of God and the sacrifice He made for humanity. As noted in John 14:6, Jesus declares Himself to be 'the way, and the truth, and the life.' His life exemplified perfection, and through His death, He bore the sins of many (Isaiah 53:5). This act of vicarious atonement not only validates His ability to save but also guarantees that believers are redeemed by His blood, as affirmed in Ephesians 1:7. Hence, our faith in Christ is anchored on His divine nature and the sufficiency of His atonement.