The following is an excerpt from The MacArthur New Testament Commentary on Ephesians 2.

For He Himself is our peace, who made both groups into one, and broke down the barrier of the dividing wall, by abolishing in His flesh the enmity, which is the Law of commandments contained in ordinances, that in Himself He might make the two into one new man, thus establishing peace, (Ephesians 2:14–15)

Christ forever broke down (the Greek aorist tense signifies completed action) every dividing wall by abolishing in His flesh the enmity, which is the Law of commandments contained in ordinances. When Jesus died on the cross He abolished every barrier between man and God and between man and his fellow man. The greatest barrier between Jew and Gentile was the ceremonial law, the Law of commandments contained in ordinances. The feasts, sacrifices, offerings, laws of cleanliness and purification, and all other such distinctive outward commandments for the unique separation of Israel from the nations were abolished.

That God’s moral law was not abolished is clear from the phrase contained in ceremonies. His moral law reflects His own holy nature and therefore can never change (cf. Matt. 5:17–19). That is the law which for the Jews was summarized in the Ten Commandments and which for all men is written on their hearts (Rom. 2:15) and still commanded of them (Matt. 22:37–40; Rom. 13:8–10). Jesus summarized God’s moral law still further by declaring, “A new commandment I give to you, that you love one another, even as I have loved you” (John 13:34). The Ten Commandments, like all of God’s moral laws, are but the structured and particularized love that God still requires (James 2:8).

All the ceremonial laws which distinguished and separated Jews from Gentiles were obliterated. Before Christ those groups could not eat together because of restricted foods, required washings, and ceremonial contamination. Now they could eat anything with anyone. Before Christ they could not worship together. A Gentile could not fully worship in the Jewish Temple, and a Jew would not worship in a pagan temple. In Christ they now worshiped together and needed no temple or other sacred place to sanctify it. All ceremonial distinctions and requirements were removed (cf. Acts 10:9–16; 11:17–18; Col. 2:16–17), that in Himself He might make the two into one new man, thus establishing peace. The emphasis is again on in Himself, affirming that this new unity can occur only when men are united in the person of the Lord Jesus Christ.

Do not think that I came to abolish the Law or the Prophets; I did not come to abolish, but to fulfill. (Matthew 5:17)

Of primary concern to every faithful Jew seeking to evaluate Jesus was, “What does He think of the law; what does He think of Moses and the prophets?” The leaders often confronted Jesus on matters of the law. Many Jews believed that the Messiah would radically revise or completely overturn the Mosaic law and establish His own new standards. They interpreted Jeremiah 31:31 as teaching that God’s new promised covenant would annul the old covenant and start over on a completely new moral basis. Sickened of the demanding, hypocritical legalism of the Pharisees, many people hoped the Messiah would bring in a new day of freedom from the burdensome, mechanical, and meaningless demands of the traditional system.

The Law and the Prophets represent what we now call the Old Testament, the only written Scripture at the time Jesus preached (see Matt. 7:12; 11:13; 22:40; Luke 16:16; John 1:45; Acts 13:15; 28:23). It is therefore about the Old Testament that Jesus speaks in Matthew 5:17–20. Everything He taught directly in His own ministry, as well as everything He taught through the apostles, is based on the Old Testament. It is therefore impossible to understand or accept the New Testament apart from the Old.

Jesus’ warning, do not think, indicates that most, if not all, of His hearers had a wrong conception about His teaching. Most traditionalistic Jews considered the rabbinic instructions to be the proper interpretations of the law of Moses, and they concluded that, because Jesus did not scrupulously follow those traditions, He obviously was doing away with the law or relegating it to minor importance. Because Jesus swept away the traditions of washings, special tithes, extreme Sabbath observance, and such things, the people thought He was thereby overthrowing God’s law. From the outset, therefore, Jesus wanted to disabuse His hearers of any misconceptions about His view of Scripture.

Kataluo (abolish) means to utterly overthrow or destroy, and is the same word used of the destruction of the Temple (Matt. 24:2; 26:61; etc.) and of the death of the physical body (2 Cor. 5:1). The basic idea is to tear down and smash to the ground, to obliterate completely. In several places, as here, the word is used figuratively to indicate bringing to naught, rendering useless, or nullifying (see Acts 5:38–39; Rom. 14:20). Doing that to God’s law is the antithesis of the work and teaching of Jesus.