Man's heart rebels against the need of the grace of God. He thinks that, in some way or other, his own arm can bring salvation to him.
But how clear is the Word of God! Salvation is "Not of works, lest any man should boast," Eph. 2:9.
If by our own reformation, or goodness, or merit we could earn salvation, then we might well boast of what we had done.
But this can never be. "To him that worketh is the reward not reckoned of grace, but of debt. But to him that worketh not, but believeth on Him that justifieth the ungodly, his faith is counted for righteousness." Rom. 4:4, 5.
Good works, which follow salvation, do have a most important place. But they cannot earn salvation. Salvation comes first, as a gift, by the free grace of God. Then, and not until then, good works will flow from that salvation, and be known and enjoyed. The tree of salvation comes first then the fruit of good works will grow on that tree. "Not by works of righteousness which we have done, but according to His mercy He saved us." Titus 3:5.