How do we know that Jesus has the power to cleanse sins?

Jesus' power to cleanse sins is rooted in His divine nature as the God-man and the efficacy of His sacrificial death. In Colossians 1:22, it states that through Christ's death, believers can be presented holy and blameless before God. This cleansing comes from faith in Him, as stated in 2 Timothy 1:12, where Paul expresses confidence in Christ's ability to keep that which has been committed to Him. The leper in Mark 1 comes to Christ believing in His ability to cleanse him, highlighting the faith necessary to trust in Christ's power. The work of Christ on the cross secured the full payment for sin, allowing those who believe to be justified and cleansed eternally.