What does the Bible say about the impossibility of being saved by works?

In Hebrews 10:1-4, the writer asserts that it is 'not possible' for the blood of bulls and goats to take away sins. This declaration highlights the futility of attempting to achieve salvation through works. God makes it clear that human efforts, no matter how noble, can never suffice to atone for sin. The sacrifices mentioned in the Old Testament served merely as shadows, pointing to the ultimate sacrifice of Christ, which is what actually removes sin. If salvation could be attained through our actions, then the atoning death of Christ would have been unnecessary.