Since the Enlightenment it has been a common view that true religion must show its legitimacy by its moral usefulness. As an early response to this, moral theologians in the 19th century began to talk about «Christian values» in order to give a social legitimation to the faith. But to justify Christianity simply because it provides a foundation of morality, instead of showing the necessity of Christian morality from the truth of Christianity, is a very dangerous inversion.
Nevertheless, it is true that the three so-called cardinal virtues – faith, hope and love (1 Cor. 13:13) – are natural virtues in the sense that they express qualities needed to uphold both the individual and communal life as such. But there is more to be said. The revolutionary message of the Gospel is that Christ transforms everything by renewing man’s living contact with God. By bringing human nature back to God, Christian life is not the antithesis of the natural. The difference the gospel makes, is giving mankind a new status in a covenant with God our Creator.
Already the ethics of the Decalogue is based on the idea of a new status between God and the people of Israel. The premise, the framework around the commandments, is that God’s mighty deeds have made the chosen people free: “I am the LORD your God, who brought you out of Egypt, out of the land of slavery.» What God demands for Himself is that the Hebrews be faithful: “You shall have no other gods before me» (Ex 20:2f). Among themselves they must live a decent life according to their new status: Because they are no longer slaves but free, the people of Israel must live as men of honor and show respect for their parents and abstain from murder, whoring, stealing and lying. However, these precepts are the rules of decent behaviour among gentlemen in any culture. The motivation is nevertheless specific because it is founded on the new status given in the covenant with God. Without this starting-point also Christian ethics are easily reduced to humanistic altruism.
The relationship between natural virtues and spiritual gifts becomes clear when St. Paul speaks of the fruit of the Spirit over against the work of the flesh. The Apostle exemplifies the work of the flesh among other sins as adultery, lewdness, hatred, selfish ambitions and envy. «By contrast», writes the Apostle, «the fruit of the Spirit is love, joy, peace, patience, kindness, generosity, faithfulness, gentleness, and self-control. There is no law against such things» (Gal 5:22f). Nobody can with reason maintain that these virtues are exclusively the privilege of Christians or deny that the work of the flesh takes its toll also on the believers.
This leads to the question: Is there then no specific Christian ethics – only spiritually qualified human virtues? The answer must be a clear yes and no!
The point is that by living and walking in the Spirit, the believer is invited to transcend himself and enter a «zone» of divine being and activity. Thus by imparting the Spirit into the faithful, God renews their humanity (Gal 5:16ff).
The moral challenge for Christians – like the people of the Old Covenant – is to live up to our new status as God’s children. Christ must be formed in us, explains the Apostle (Gal 4:19). To clarify this imitation of Christ, St Paul uses the the word «worthy». He admonishes the Philippians: «Let your conduct be worthy of the Gospel of Christ» (1:27). Likewise he beseeches the Ephesians: «to walk worthy of calling with which you have been called» (4:1). And the Colossians are told to »walk in a manner worthy of the Lord, to please him in all respects, bearing fruit in every good work» (Col. 1:10). Furthermore, he impresses upon the Thessalonians: «Walk in a manner worthy of God who calls you into his kingdom and glory» (1 Thess 2:12).
Using the word «worthy» to qualify Christian living, the Apostle seems to refer back to God’s demands of the people of Israel at Sinai. In both cases the moral claims are based on the dignity given in new status before God. Our self-respect as believers must be manifested in a worthy way of life in the eyes of God and mankind.