One way of approaching Ephesians two is to see it structurally describing a series of "before"  something and "after" states. The "before" in verse 1 is "dead through your trespasses and sins."  The "after" is made alive. "Before," the writer says, "ye were dead through your trespasses and sins...[and] ...walked according to the course of this world, according to the prince of the powers of the air, of the spirit that now worketh in the sons of disobedience."  The writer says this "before" state was once the state of all: "we also once lived in the lust of our flesh, doing the desires of the flesh and of the mind, and were by nature children of wrath, even as the rest." Then, "God, being rich in mercy, loved us" in the before state of being "dead through our trespasses." In the "after" state, "we...are made alive together with Christ (by grace have ye been saved)," raised up, made to sit in the heavenly places in Christ Jesus:

The writer also explains why this transformation has occurred: "that in the ages to come he [God] might show the exceeding riches of his grace in kindness toward us in Christ Jesus... his workmanship, created in Christ Jesus for good works, which God afore prepared that we should walk in them." Note that the "afore prepared" echoes 1.4 that these were "chosen before the foundation of the world."

A second section of  "before"  and "after begins with Ephesians 11, where "before" is separated from Christ), and the "after"  is brought near in the blood of Christ.

Eph 2:11 Wherefore remember, that once ye, the Gentiles in the flesh, who are called Uncircumcision by that which is called Circumcision, in the flesh, made by hands;

Eph 2:12 that ye were at that time separate from Christ, alienated from the commonwealth of Israel, and strangers from the covenants of the promise, having no hope and without God in the world.

Please note that the author addresses gentiles, the Uncircumcision, alienated from the commonwealth of Israel, strangers from the covenants of the promise. The before Christ is alienation, no hope, no God.  The next section begins but now:

Eph 2:13 But now in Christ Jesus ye that once were far off are made nigh in the blood of Christ.

Eph 2:14 For he is our peace, who made both one, and brake down the middle wall of partition,

Eph 2:15 having abolished in the flesh the enmity, even the law of commandments contained in ordinances; that he might create in himself of the two one new man, so making peace;

Eph 2:16 and might reconcile them both in one body unto God through the cross, having slain the enmity thereby:

Eph 2:17 and he came and preached peace to you that were far off, and peace to them that were nigh:

Eph 2:18 for through him we both have our access in one Spirit unto the Father.

The gentiles who were alienated now in Christ Jesus are brought near "in the blood of Christ." Christ is the mediator who has broken  "down the middle wall of partition." This middle wall of partition is the one dividing gentiles from Jews, the Circumcision, the commonwealth of Israel, the children of the covenants of promise. This Christ is a mediator of peace. The two have been made one. How was this accomplished? Christ in the flesh abolished enmity, "even the law of commandments contained in ordinances," to create in himself "of the two one new man, so making peace." How did he accomplish this? He reconciled "them both in one body onto God through the cross." The message Christ preached was that of peace to the gentiles, "you that were far off," and peace to the Jews, "to them that were night." The two have been joined in unity: "for though him we both have our access in one Spirit onto the Father."

The result of the transformation is that Jews and gentiles are no more strangers and so-journers but fellow-citizens "with the saints, and of the household of God." Both are built "upon the foundation of the apostles and prophets." Continuing the metaphor of foundational structure, the writer says Christ (recall before the foundation of the world) is the chief corner stone. Different buildings are being "fitly framed together" to grow (note the switch to an organic metaphor) into a holy temple, built together "for a habitation of God in the Spirit"

Eph 2:19 So then ye are no more strangers and sojourners, but ye are fellow-citizens with the saints, and of the household of God,

Eph 2:20 being built upon the foundation of the apostles and prophets, Christ Jesus himself being the chief corner stone;

Eph 2:21 in whom each several building, fitly framed together, groweth into a holy temple in the Lord;

Eph 2:22 in whom ye also are builded together for a habitation of God in the Spirit.

 

The Net Bible offers yet another structural approach: new life individually and new life corporately:

New Life Individually

2:1And although you were1 dead2 in your transgressions and sins, 2:2 in which3 you formerly lived4 according to this world's present path,5 according to the ruler of the kingdom6 of the air, the ruler of7 the spirit8 that is now energizing9 the sons of disobedience,10 2:3 among whom11 all of us12 also13 formerly lived out our lives in the cravings of our flesh, indulging the desires of the flesh and the mind, and were by nature children of wrath14 even as the rest...15

2:4 But God, being rich in mercy, because of his great love with which he loved us, 2:5 even though we were dead in transgressions, made us alive together with Christ--by grace you are saved!16-- 2:6 and he raised us up with him and seated us with him in the heavenly realms in Christ Jesus, 2:7 to demonstrate in the coming ages17 the surpassing wealth of his grace in kindness toward18 us in Christ Jesus. 2:8 For by grace you are saved19 through faith,20 and this is not of yourselves, it is the gift of God; 2:9 it is not of works, so that no one can boast.21 2:10 For we are his workmanship, having been created in Christ Jesus for good works that God prepared beforehand so we may do them.22

The individual is dead in transgressions and sins, living according to the world, energized into disobedience, living in the cravings of flesh, indulging the desires of flesh and mind--by nature, children of wrath. Next, the writer brings these individuals together corporately:

New Life Corporately

2:11 Therefore remember that formerly you, the Gentiles in the flesh--who are called "uncircumcision" by the so-called "circumcision" that is performed in the body23 by hands--2:12 that you were at that time without the Messiah,24 alienated from the citizenship of Israel and strangers to the covenants of promise,25 having no hope and without God in the world. 2:13 But now in Christ Jesus you who used to be far away have been brought near by the blood of Christ.26 2:14 For he is our peace, the one who turned both groups into one27 and who destroyed the middle wall of partition, the hostility, in his flesh, 2:15 when he nullified28 the law of commandments in decrees. He did this to create in himself one new man out of two,29 thus making peace, 2:16 and to reconcile them both in one body to God through the cross, by which the hostility has been killed.30 2:17 And he came and preached peace to you who were far off and peace to those who were near, 2:18 so that31 through him we both have access in one Spirit to the Father. 2:19 So then you are no longer foreigners and non-citizens, but you are fellow citizens with the saints and members of God's household, 2:20 because you have been built32 on the foundation of the apostles and prophets,33 with Christ Jesus himself as34 the cornerstone.35 2:21 In him36 the whole building,37 being joined together, grows into a holy temple in the Lord, 2:22 in whom you also are being built together into a dwelling place of God in the Spirit.

The new, corporate life is built on the foundation of the apostles and prophets (new and old), with Jesus Christ as the cornerstone. In Christ, the whole building, consisting of parts, is joined together and "grows" into a holy temple in the Lord, "a dwelling place of God in the Spirit."

Deserving attention is 2.15:

Eph 2:15 having abolished in the flesh the enmity, even the law of commandments contained in ordinances; that he might create in himself of the two one new man, so making peace;

and who destroyed the middle wall of partition, the hostility, in his flesh, 2:15 when he nullified28 the law of commandments in decrees. (RSV)

The reader may wish to recall Romans 3.21-31:

Rom 3:21 But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;

Rom 3:22 Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:

Rom 3:23 For all have sinned, and come short of the glory of God;

Rom 3:24 Being justified freely by his grace through the redemption that is in Christ Jesus:

Rom 3:25 Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God;

Rom 3:26 To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.

Rom 3:27 Where is boasting then? It is excluded. By what law? of works? Nay: but by the law of faith.

Rom 3:28 Therefore we conclude that a man is justified by faith without the deeds of the law.

Rom 3:29 Is he the God of the Jews only? is he not also of the Gentiles? Yes, of the Gentiles also:

Rom 3:30 Seeing it is one God, which shall justify the circumcision by faith, and uncircumcision through faith.

Rom 3:31 Do we then make void the law through faith? God forbid: yea, we establish the law.

The temptation all too often is to stress the law as nullified, abolished. A note in the Net Bible translates nullified as rendered inoperative: "28tn (2:15) Or "rendered inoperative." Romans makes clear what the process is: the law is established, and it is one law of faith: "one God, ...shall justify the circumcision by faith, and uncircumcision through faith." The writer then asks, "Do we make voice the law through faith?" and answers: "God forbid: yea, we establish the law." What the writer is saying is that it has always been one law: the law of faith in God. What is abolished is the law of works, externality rather than internality. The Oxford Companion worries through the tangled way in which the Greek nomos identifies Torah with law and the way Paul in which Paul uses the term both positively and negatively (422 ff). Positively, the law addresses ethics and authority and decent community life and the standard for behavior; negatively, the law equals the "old aeon" of "sin, flesh, and death" opposed to Christ's death, resurrection, and imminent parousia. The Gospels, written later than Paul's epistles, build upon a negative attitude toward the law. The Hebrew word Torah, translated as law, refers to teaching and instruction, God's demands upon the Israelite people. In the RSV, Ephesians 2.15, what is nullified is "the law of commandments in decrees." In the KJV, it is the "law of commandments contained in the ordinances." The Companion identifies statutes, ordinances, and commandments as terms "belonging to the legal sphere" and referring "to specific practices and enactment." In New Testament views, "'the Law' received widely divergent treatment" in the "charged and changing context" where a new religious movement sought to "define and eventually to distinguish itself from Greek-speaking synagogue communities" (423). The unity intended the writer of Ephesians summarizes in chapter five:

Eph 4:4 There is one body, and one Spirit, even as ye are called in one hope of your calling;

Eph 4:5 One Lord, one faith, one baptism,

Eph 4:6 One God and Father of all, who is above all, and through all, and in you all.

Eph 4:13 Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ:

One will recall that Jesus in Mark reduced the law to two parts:

Mar 12:29 And Jesus answered him, The first of all the commandments is, Hear, O Israel; The Lord our God is one Lord:

Mar 12:30 And thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind, and with all thy strength: this is the first commandment.

Mar 12:31 And the second is like, namely this, Thou shalt love thy neighbour as thyself. There is none other commandment greater than these.

In Romans, the righteousness of God is manifest by the Law and the prophets and by Jesus Christ. The one law is faith in God.