In his writings about the blessings of the New Covenant ministration of the Spirit, the apostle Paul contrasts two particular sayings of Moses that illustrate a point of difference between the righteousness lived out by the old law system versus a righteousness that is lived out by bold faith in God within the New Covenant heavens and earth. Paul writes:

Christ is the end of the law for righteousness to everyone who believes. For Moses writes about the righteousness of the law: "The one who does them will live by them." But the righteousness which is of faith says this: "Don't say in your heart, 'Who will ascend into heaven?' (that is, to bring Christ down); or, 'Who will descend into the abyss?' (that is, to bring Christ up from the dead.)" But what does it say? "The word is near you, in your mouth, and in your heart;" that is, the word of faith, which we preach (Rom 10:4-8)

In this passage, Paul categorizes Moses' statement in Leviticus 18:5 (echoed elsewhere in Deuteronomy 5:33) as expressing a righteousness which is of the law—"the one who does them will live by them." In contrast, Paul categorizes Moses' statement found in Deuteronomy 30:11-14 as typifying a righteousness which is of faith—"The word is near you, in your mouth and in your heart." The contrast Paul seeks to illustrate is clear: the Leviticus 18:5/Deuteronomy 5:33 passage speaks of a system of "righteousness of the law" whereas the Deuteronomy 30:11-14 passage embodies "righteousness which is of faith." Note Paul's contrast:

Paul, addressing kindred Jews familiar with the Old Covenant system, is using concepts expressed within the Old System to teach his contemporaries the essence of the New Covenant righteousness, faith, and practice. His teaching was timely because the new covenantal system and righteousness was being ushered in during their generation, supplanting the Old Covenant world. We can look at the parallel passage put forth in Paul's letter to the Church at Galatia in Galatians 3:11-12 to even further illustrate what Paul is saying to them. In the Galatians passage, Paul contrasts Leviticus 18:5 against the statement of the prophet Habakkuk that "the righteous shall live by faith." Paul proclaims:

that no one is justified by the Law before God is evident; for, "the righteous man shall live by faith." However, the Law is not of faith; on the contrary, "he who practices them shall live by them." (Galatians 3:11-12)

Again, Paul quotes Leviticus 18:5, categorizing it as expressing a mode of religion contrary to living by faith. Paul consistently classifies Leviticus 18:5 as an expression typifying the "righteousness of the law." In light of the clear delineation between these two opposite modes of religious practice before God (both having been expressed under the Old system), a proper understanding of what each of these opposing modes entails goes a long way towards understanding the riches of New Covenant living.

Righteousness of Faith: A Look at Deuteronomy 30:11-14

In Deuteronomy 30:11-14, Moses tells the people that God's demands concerning righteousness and justice were placed in their hearts that they might do them. That is, God's expectations of righteousness and justice (as codified at that time in Mosaic law) actually were to reside in the conscience of God's people. According to Moses, the principle concepts of righteousness and justice are not something external and unable to be grasped, but something internal and intuitive which God granted to His Chosen ones to be followed from within. A good conscience before God would enable them to follow the Mosaic prescriptions lawfully, recognizing the spirit in which the laws were written and applying them properly in diverse situations.

This issue of having God's law written internally on the heart is essential. If the intent and spirit of laws are not grasped, enforcement can violate the original intent. We note, for example, that every time Jesus made an apparent exception to following the "letter of the law" (i.e., strictest enforcement of what was written -- 2 Cor 3:6), he explains Himself, not by going to the letter of the law but by going to the principle from which the code sprang (e.g., Matt 12:11-12). This shows us that written laws, by nature, act upon antecedent spiritual principles of righteousness, justice, love or reconciliation that God speaks directly into men by His Spirit. As was proven by the Pharisees in Christ's day, following external laws can become lost in legalism, resulting in cases where the letter of the written law is enforced while the principle or spirit of the law gets violated (see Christ's indictment of the Pharisees in 23:13-33). By emphasizing Deuteronomy 30:11-14, Paul points to where the antecedent principle of all righteousness is located. Righteousness lies within God's people by faith and is instructed by God's Spirit. The principle concepts of God's will, which normally manifest in prescriptive codifications for society, reside internally and intuitively within the Chosen as "laws written on the heart" (Rom 2:15; Heb 8:10). We might associate this with "good conscience," or "abiding by the spirit of the law," or think of it as "inward righteousness," or being a "just person," but Paul calls it "Christ"—Christ "in our hearts and in our mouths" (Rom 10:6-8; Col 1:27). Therefore, Moses was pointing the Israelites to a righteousness by faith that God places inwardly in his Chosen ones that they might live lives pleasing to Him. Such practice of faith in the Spirit enables God's people to realize the fullness of the covenant promises.

Righteousness of the Law: A Look at Leviticus 18:5

We have just examined how Deuteronomy 30:11-14 exemplifies "righteousness which is of faith." Now we must look at Leviticus 18:5 and its significance in Paul's theology. On at least two occasions Paul seems to say that Leviticus 18:5 is the very essence of "righteousness which is of the law" (Rom 10:5; Gal 3:12). As such, it is not the guiding principle for New Covenant living. But what does Leviticus 18:5 mean? Why does Paul consider it an opposite to righteousness by faith? To understand the significance of Leviticus 18:5, it helps to understand under what circumstances the Israelites were given the instruction. Moses, in Deuteronomy 5:22-33, recounts the tragic history of the Israelites when, due to the awesome display of God's glory at Mt. Sinai, the people unanimously opted to reject hearing directly from God, pleading instead for Moses to do this on their behalf (Deut 5:4-5,23-33). Instead of wanting a "face-to-face" relationship with God such as Moses had, the Israelites wanted their leader to mediate for them and provide a written version of God's instruction to be followed as substitutionary for direct relations (Deut 5:4-5,23-33;Ex 19:12-20:21). The vast majority of the Israelites weren't ready to follow God directly as Moses followed (Deut 5:25-28), and Yahweh lamented over this. Due to their own stubbornness, they had become afraid of God's Holy Presence to the point of choosing Moses to be their only direct contact with God (Deut 5:28-33). Once Moses was dead, later generations of Israelites continued to know God through the written code and system which Moses had left to mediate between God and man. Therefore, Paul sees Leviticus 18:5/Deuteronomy 5:29-33 as expressing a practice of righteousness mediated by law and distanced from bold faith before God such as Moses had. They said: "if we hear the voice of the Lord our God anymore, then we shall die...You go near and hear all that the Lord our God may say, and tell us all that the Lord our God says to you and we will hear and do it" (Deut 5:25,27). As a result of their rejection, the Lord God spoke directly only to Moses while the rest were separated from God's manifest, personal Presence (Deut 5:29-31). Such distance is incompatible with God's desire that we know Him inwardly and directly through Christ, the teacher and guide of our consciences. Abiding in the glory of God's presence was not something out of reach for the Israelites; after all, they did witness it "face-to-face" at Sinai (Deut 5:4). Additionally, Moses followed God and received the righteous codes directly in such a direct manner. It was, therefore, possible that the rest of the Israelites could have had this blessedness; yet they rejected hearing from God whereas Moses didn't (Deut 5:22-33).

Conclusion

Leaving behind Leviticus 18:5, the essence of righteousness by external mediation of the law and not the righteousness which is of faith, we press on to orient ourselves to the greater glory of New Covenant living. As Moses instructed, we seek to live by faith in God and have His laws written on our hearts that we might do them. Indeed, we affirm that Christ himself is in our hearts and mouths (Rom 10:6-8; Col 1:27; Eph 3:14-21), the Spirit teaching us to hear and obey even as Moses was taught to hear and obey. The Israelites of that day chose to live by an external mediation of written law while refusing God's manifest presence. As the covenant people of God today, however, we glory in the Presence of our God and worship Him in spirit and in truth, "following the word that is very near to us, in our mouths and in our hearts, that we may observe it" (Deut 30:11-14).