Ephesians 2:11-18 is the best Biblical reference I know of that shows the 2 groups, Gentiles and Jews, merging and becoming one.
From the NWT:
"Therefore keep bearing in mind that formerly YOU were people of the nations as to flesh; “uncircumcision” YOU were called by that which is called “circumcision” made in the flesh with hands— 12 that YOU were at that particular time without Christ, alienated from the state of Israel and strangers to the covenants of the promise, and YOU had no hope and were without God in the world. 13 But now in union with Christ Jesus YOU who were once far off have come to be near by the blood of the Christ. 14 For he is our peace, he who made the two parties one and destroyed the wall in between that fenced them off. 15 By means of his flesh he abolished the enmity, the Law of commandments consisting in decrees, that he might create the two peoples in union with himself into one new man and make peace; 16 and that he might fully reconcile both peoples in one body to God through the torture stake, because he had killed off the enmity by means of himself. 17 And he came and declared the good news of peace to YOU, the ones far off, and peace to those near, 18 because through him we, both peoples, have the approach to the Father by one spirit."