How do we know that salvation is only by faith?

Scripture asserts that we are justified by faith apart from the works of the law (Romans 3:28). Salvation is a gift that we receive through faith, as demonstrated in Galatians 4:4-5, where Paul emphasizes that Christ was sent to redeem us so that we might receive adoption as sons. Our faith is not a work that we do to earn salvation; rather, it acknowledges the completed work of Christ on our behalf. Thus, faith is the means through which we attain salvation, affirming that our acceptance with God rests solely in what Christ has accomplished.