The Abiding Validity of the Law in Exhaustive Detail – Part 1.

In chapter two of Theonomy in Christian Ethics, Greg Bahnsen lays out the theonomic thesis and its biblical support found in what he considers to be the locus classicus of Theonomy, Matthew 5:17-19; in this passage Jesus teaches His relation to the law of the Older Testament, the law’s status in the New Testament, and how his disciples should respond to the law. A technical analysis of the locus classicus leads us to the inescapable conclusion that Jesus taught that the Older Testament law’s validity is abiding including it’s every exhaustive detail (p. 41). The following is my summation of Bahnsen’s lexicographical study of Matthew 5:17-19. The credit goes fully to him for discovering and collecting the Biblical data used to shed light on Jesus’ relation to the law of God and what that means for Christians today.  

The passage from Matthew reads as follows:

17 “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. 18 For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished. 19 Therefore whoever relaxes one of the least of these commandments and teaches others to do the same will be called least in the kingdom of heaven, but whoever does them and teaches them will be called great in the kingdom of heaven” (Matthew 5:17-19).

Do not think…

Jesus starts this section with a word of prohibition, “Do not think…” The Greek uses the aorist tense which gives the verb an aggressive force: “do not (begin to) think” as opposed to “stop thinking” which would need to be expressed in the present tense (p. 49). The point is Christ knew the possibility that His hearers or scribal opponents might distort His teaching of the law, and so instructs them not to begin to think that the Messiah came to abolish the law of God.


The sense of καταλύω or abolish is that of dismantling or destroying something by separating its pieces. Later Matthew applies the term to the demolition of a temple (cf. 24:2; 26:61; 27:40). The same Greek word is used in 2 Maccabees where we read “… and restored the laws which were on the point of being destroyed” (2 Mac 2:22), and “… and abrogating the lawful ways of living he introduced new customs contrary to the law” (2 Mac 4:11). the Didache also uses καταλύω to describe how false teachers undermine or abolish apostolic teaching (11:2).

καταλύω never takes the meaning “disobey or violate”, rather Jesus uses the metaphor to teach that His relationship to the law is NOT one of invalidation or abrogation (p. 50).

The Law or the Prophets

Although the phrase “law or prophets” refers to the Older Testament canon as a whole, there is good reason to hold that the phrase is best taken as focusing on its ethical stipulations contained within. The context of Matthew clearly demonstrates that both “law and the prophets” refer to divine demand and not prophecy or promise. The proceeding verse deals with “good works”; and throughout the entire sermon Jesus expounds upon laws found in the Torah and the prophet’s divine application of them (as we will examine in future posts). Later on in the sermon, he bookends his exposition on various Older Testament laws and prophetic teaching by using the terms “law” and “prophets” once again with an ethical connotation;

“So whatever you wish that others would do to you, do also to them, for this is the Law and the Prophets” (Matt 7:12).

While “law or prophets” broadly denotes the Older Testament scriptures, Jesus’ stress is upon the ethical content, the commandments of the Older Testament (p. 53). Thus Jesus did not come to change the moral principles or relax the claims of justice found in the law and the prophets. If Jesus did not come to abolish the standing law of the Older Testament, then what is His relation to the law?


While Jesus proclaims and repeats His proclamation that he did not come to abrogate the law, He states in sharp contrast that He came to “fulfill” it instead. πληρόω (fulfill) might be the most important term in the locus classicus because it directly describes Jesus’ relation to the law. But what exactly did Jesus mean by “fulfill”? Several suggestions as to what Jesus meant by “fulfill” include: (1) ending, (2) replacing, (3) supplementing, (4) obeying, or (5) enforcing or confirming the ethical stipulations of the Older Testament.

The first suggestion (i.e., “put an end to”) contains a rather obvious problem for the reason that it makes Christ contradict himself. It has already been shown that καταλύω means abrogate, which would make the passage read, “I came not to abrogate the law, but to abrogate it” (p. 57).

The second suggestion (i.e., “replace”) holds that Jesus brings in the law of the Spirit which conceals the law of the letter, and so Jesus, like the Old Testament prophets teaches an attitude rather than a moral code (p. 59). This view overlooks the fact that God’s law was the basis for the prophet’s charge against the people, religious leaders, rulers, or even nations and so we cannot dismiss the idea of a legal code. Furthermore, Jesus affirms every detail of the Older Testament law in verse 18 which indicates our interpretation principle must be of continuity and not discontinuity.

The third suggestion (i.e., “supplement”) takes the sense of “adding to” the law and the prophets. According to this interpretation Jesus begins where the Old Testament leaves off and reveals what the more perfect will of God is for the lives of Christians. Moreover, the Old Testament law was inadequate for revealing inward obedience, so Jesus had to reveal the law’s intrinsic standards of righteous living. Jesus was perfecting the law.

This interpretation appears to have potential only when the Older Testament testimony about the law’s inward workings and perfection is ignored. For Example, the Psalmist under the inspiration of the Holy Spirit says that the law is perfect (Psa 19:7) and that every one of its rules are righteous (Psa 19:9). How can Jesus perfect what is already perfect?

Additionally, the law already established its intrinsic attribute. In Moses’ second reading of the law he states that all the commands “shall be on your heart” (Deut 6:7). The Older Testament law required obedience from the heart no different from what is required from New Covenant believers today. For example, just as Jesus warns against thinking evil thoughts against another (Matt 5:21-22), so does the Older Testament (Psa 24:11; 35:4; Prov 12:20; 14:22). This is why Jesus could rebuke the pharisees. Their wicked hearts were already held accountable to God’s holy law which exposed matters of the heart.

The fourth suggestion (i.e., “obey”) takes “fulfill” to mean that Jesus came to carry out or be obedient to the law, by which the usual implication from this interpretation is that Jesus came to obey the law where we fail to do so. This is certainly true, Christ did meet the righteous requirements of the law on our behalf and those who have faith in Him are imputed His perfect obedience, however, this doctrine is not in mind here. It is not Christ’s obedience that is in question here, but rather His position and stance on the law. Nowhere in the entire sermon does Jesus explain or elaborate on the doctrine of Imputed Righteousness. To associate Jesus’ use of “fulfill” with imputed righteousness is to impose another teaching of Scripture in the wrong place.

The final suggestion as to the meaning of “fulfill” is extracted from the antithesis of “abolished,” which would be that Jesus came to confirm or establish the Older Testament law.

To interpret “fulfill” as being in direct opposition to “abolish” is appropriate because of Matthew’s use of ἀλλά (sharp contrast) instead of δέ (general contrast). We see a very similar statement later in Matthew’s Gospel when Jesus says, “Do not think that I have come to bring peace to the earth. I have not come to bring peace, ἀλλά a sword” (Matt 10:34). In this verse “peace” and “sword” are presented as sharply opposed to one another, and so we should expect the same with the terms “abolish” and “fulfill.”

A failure to acknowledge the sharp contrast between “abolish” and “fulfill” results in an unintelligible shift in categories. Bahnsen comically used the following nonsensical phrases as examples to illustrate the incoherence had Jesus switched categories: “he is not Russian, but third to bat”; “she is not left handed, but very sad; “he did not come to repudiate the Koran, but to play piano.” To not recognize the sharp contrast drawn out by Jesus’ phrase risks muddling His intended contradicting terms (pp. 68-69).

Scriptural examples of “fulfill” being used to mean established.

Examination of the use of πληρόω (fulfill) in Greek demonstrates that the term took the meaning of “confirm” or “established” in some instances. It is used this way at least twice explicitly in the Septuagint (cf., 3 Kings 1:14; 1 Mac 2:55). Since the Septuagint was translated around 250 B.C., from at least that time on the use of πληρόω to mean “confirm” was in circulation; hence that particular use would have been available to Jesus and Matthew (pp. 70-71).

A few New Testament passages can also be adduced to demonstrate that fulfill can take the sense of “confirm, establish.” In 2 Corinthians 10:6 Paul states that he will take action against all disobedience, but only “when your obedience is fulfilled,” that is, when the obedience of his readers is a standing fact. To “fill up” obedience is equivalent to confirming or establishing obedience. The same idea is expressed in Revelation 3:2 where Christ says that He has not found the Sardisians’ “works (plural; not “work” in the sense of mission) having been fulfilled before God.” In Romans 15 Paul says that lest he build upon another man’s foundation (v. 20), he has established the gospel message from Jerusalem to around Illyricum (v. 19). Paul is not reflecting on the fullness or completeness of his teaching in reaching every single person in that territory, rather he has established the message of Christ’s gospel through out that territory. Therefore, the New Testament, in agreement with the Septuagint, is found to use “fulfill” with a variety of meanings, and one of those is that of “establish” or “confirm” (p. 72).


Given the preceding contextual and lexicographical considerations “fulfill” in Matthew 5:17 must mean “confirm.” The translation of the verse should read as follows: “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to confirm them (p. 73).

The law of God is in full force, transferred from the Older Testament to the new. Christians must obey and practice what might be considered the least command otherwise he will be called least in Christ’s Kingdom. Since it is Christ who established the law, obedience to it means obedience to Christ himself. God has not changed his standard of righteousness. God does not allow lawlessness in the New Covenant but still demands that we walk in His law.

Bahnsen’s thesis that the law of God abides down to its exhaustive detail raises many questions that must be answered, such as: what about laws pertaining to sacrifice, diet, or the cultural circumstances of Israel? What about alleged New Testament passages that seem to contradict the idea of the laws abiding validity? What about alternatives to God’s law? Does God require Civil Magistrates to obey His law? Are the penalties of the Older Testament still in force? How can we tell which laws apply today and which ones expired? If expired, how are they still valid? These are questions that are answered in Bahnsen’s book. Hopefully I will be able to summarize his thoroughly in depth Biblical responses to these question. Regarding these many questions, Bahnsen in this chapter made a very important initial point, that because of the meaning of Jesus’ statement in Matthew 5:17, we should be attempting to answer these question by finding how they fit in the grand scheme of the law’s abiding validity.  


Bahnsen, Greg L. Theonomy in Christian Ethics. 3rd ed. Nacogdoches, TX: Covenant Media Press, 2002.


Published by Ben Moore

Ben is a Christian worldview writer who holds a BA in Economics and is currently pursuing a Masters degree in Biblical studies at Reformed Theological Seminary. He and his beloved wife live and serve to see the Gospel permeate throughout all areas of life.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: