How do we know salvation by works is wrong?

In the sermon, it is articulated that the religion of works, exemplified by Cain, asserts that a person's salvation is in some way dependent on their actions, such as moral decisions or good deeds. This belief distorts the core principle of grace, which teaches that all merit comes from Christ alone. The key biblical references highlight that true righteousness can only come through faith in Christ, not through our works, thus demonstrating that the reliance on personal achievement leads to spiritual pride and condemnation rather than redemption.