Sure! Verses 3-12 are what is known as a Hebraism. It's a praise of God. In this section Paul is praising God for what He's done for the Jewish people. Take note that in verses 3-12 Paul uses first person plural pronouns, us, we, and our. Then in verse 13 he switches to second person plural pronouns, you and your. What he's done here is distinguish two different groups, us and you. He includes himself in the "us" group. The "us" group is the Jews and the "you" group is his Gentile readers. This can be seen from verse 12 among other things. In verse 12 Paul says, 'we who before hoped in the Christ'. It was the Jews who had hoped in the Christ, not the Gentiles. If you notice Paul opens the letter this way.
Paul, an apostle of Jesus Christ by the will of God, to the saints which are at Ephesus, and to the faithful in Christ Jesus: (Eph. 1:1 KJV)
Notice again, two groups. The saints and the faithful in Jesus Christ. He goes on later in the letter to identify the saints. In chapter 2 Paul draws a distinction between the Jews and the Gentiles.
11 Wherefore remember, that ye being in time past Gentiles in the flesh, who are called Uncircumcision by that which is called the Circumcision in the flesh made by hands;
12 That at that time ye were without Christ, being aliens from the commonwealth of Israel, and strangers from the covenants of promise, having no hope, and without God in the world:
13 But now in Christ Jesus ye who sometimes were far off are made nigh by the blood of Christ.
14 For he is our peace, who hath made both one, and hath broken down the middle wall of partition between us;
15 Having abolished in his flesh the enmity, even the law of commandments contained in ordinances; for to make in himself of twain one new man, so making peace;
16 And that he might reconcile both unto God in one body by the cross, having slain the enmity thereby:
17 And came and preached peace to you which were afar off, and to them that were nigh.
18 For through him we both have access by one Spirit unto the Father.
19 Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God; (Eph. 2:11-19 KJV)
Notice that he said, "you being Gentiles". The "You group" is the Gentiles. He goes on to say that the "you" group were far off. The Jews were nigh. Then he says that in Christ they, the "you" group, are no longer strangers and foreigners, but fellow citizens with the saints. The contrast was between Jew and Gentile. The Gentiles were the "you" group and have now become fellow citizens with the saints, the Jews.