The Westminster Confession of Faith rightly admits that there is a sense in which unbelievers do things that God commands. More than this, it also acknowledges that unbelievers’ actions can produce good and beneficial results for themselves and for others. In other words, in one sense unbelievers can do things that bring about the blessing of God.

Even though we can applaud unbelievers when they outwardly conform to God's commands, we have to remember that they are not truly virtuous. They are not good enough to please God or to earn the blessing of salvation. But why is this? How can actions that outwardly conform to God's commands still be sinful?

First, obedience to God's commands must be done with the proper motive. Unless a work is done with the right motive, it is not a work that God will reward with blessings. Only believers, who are indwelled by the Holy Spirit, can do works that God rewards with blessings. One reason for this is that only believers have hearts that are purified by faith. Here the Confession is speaking of God-given, saving faith that remains and grows within believers. It is the means of purification through which believers receive new and good natures. And it properly motivates believers to do good works. As James wrote in 2:14-20:

What profit is there ... if someone says he has faith but he does not have works? Can that faith save him? ... If faith has no works, it is dead... Are you willing to recognize ... that faith without works is useless?

Unless our attempts to seek God's blessings are founded on faith, we cannot please God, and therefore cannot be rewarded by him.

Second, in order for works to be good, they must be done according to the standard of the Word of God, that is, God's revelation. All Scripture places moral demands on us. Therefore, our actions must conform to the standards of all Scripture if they are to be morally good. But God's Word is even broader than Scripture. In a very important sense, God's revelation in the creation itself is also part of the standard for good works. One of the clearest places we find this idea in Scripture is Romans 1:20:

Since the world’s creation, God's invisible attributes — his eternal power and divine nature — have been clearly seen, being understood through the things that have been made, so that men are without excuse.

And third, it must be done with the proper goal in mind, namely, to glorify God. One such example appears in Paul’s instructions about eating meat sold in the marketplace. Paul allowed that both eating and abstaining could be good things to do, as long as God's glory was respected. He wrote these words in 1 Corinthians 10:31:

Whether you eat or drink or do anything else, do everything for God's glory.

Paul understood that some immediate goals might make it good to eat, while different immediate goals might make it good to abstain from eating. His point was that there ought to be another principle overriding these immediate goals, namely a concern for God's glory, and that unless this ultimate goal were in sight, neither eating nor abstaining could be considered good. In fact, this verse suggests that God is ultimately glorified in everything that exists whether by creating it, sustaining it, governing it, empowering it, or receiving it as service in his honor. It should be no surprise, then, that he approves of works intended to bring him glory, and that he condemns works that disregard or oppose his glory. God rewards and approves only those works that have his glory as their ultimate goal.