How do we know salvation is of Christ alone?

Salvation is of Christ alone because He is the fulfillment of the law, and our justification before God is not based on our works but solely on His grace and mercy. Ephesians 2:8-9 states, 'For by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast.' Christ’s work was not only a possibility of salvation; it was a complete and effective accomplishment. As stated in John 19:30, 'It is finished,' highlighting that nothing is required from us to add to His work.