How do we know Christ's authority over sin is true?

The authority of Jesus Christ over sin is demonstrated through His miracles, particularly in His interaction with the leper in Luke 5. When the leper approached Jesus, he acknowledged Him with the words, 'Lord, if thou wilt, thou canst make me clean,' expressing faith in Christ’s ability to heal. Jesus responded affirmatively, touching the leper, which was contrary to the law that deemed the leper unclean. This act not only showed His compassion but also demonstrated His divine authority to cleanse, which fulfills the law rather than contradicts it. Thus, Christ’s miracles serve as signs pointing to His greater mission of providing spiritual healing and redemption for sinners, confirming His position as the Messiah and the fulfillment of the law.