What does the Bible say about salvation by works?

The Bible categorically teaches that salvation cannot be attained through human works or efforts. In Matthew 23, Jesus rebukes those who actively seek salvation by their own deeds, calling them serpents and vipers, and declaring their efforts futile. The only way of salvation is through grace alone, as seen in Ephesians 2:8-9, which states that it is by grace we are saved, not of works lest any man should boast. The distinction between the ways of Abel and Cain further illuminates this teaching; Abel offered a blood sacrifice as a foreshadowing of Christ, while Cain's offering represented self-righteousness and works. Thus, the Bible asserts that eternal life is a gift from God, unable to be earned or deserved by human effort.