The Believer Rewarded for Good Works

"There will be degrees of the glory of eternal life and of the blessedness of perfected salvation. These degrees of bliss and glory will be commensurate with the good works that God's people performed in their earthly lives. According as they worked out of love for God and the neighbor and in accordance with the good works they performed, they will receive from Christ the judge more splendid glory, more honorable responsibility, a higher place in the everlasting kingdom of Christ in the new creation." -David Engelsma, "Gospel Truth of Justification," pp. 389-90 

In this paragraph, Engelsma addresses the biblical truth that Christians will receive different levels of glory in the life to come in accordance with the good works we have done in this life. We see this, for example, in the words of Jesus in the Parable of the Ten Minas (Luke 19:11-27): "He said to [the first servant], 'Well done, good servant! Because you have been faithful in a very little, you shall have authority over ten cities.' And the second came, saying, 'Lord, your mina has made five minas.' And He said to him, "And you are to be over five cities'" (verses 17-18). 

What we don't see here is Jesus's offering the servants eternal life. Why? Because the unbeliever cannot do good works (Romans 3:12, Romans 14:23, Hebrews 11:6). Nowhere does the Bible describe justification as a reward for good works. Rather, good works are always the consequence of justification. No one is saved by good works; good works are what saved people do. 

As the writer of the Epistle to the Hebrews said to his readers, "Though we speak in this way, yet, in your case, beloved, we feel sure of better things - things that belong to salvation. For God is not unjust so as to overlook your work and the love that you have shown for His name in serving the saints, as you still do" (Hebrews 6:9-10). Notice to whom the writer directs his comments: to the beloved, to those who serve the saints. These cannot be qualities of unbelievers. Again, good works are something that only the believer can do, so it is impossible for any supposed good works to contribute to anyone's justification,.