Explain this:
Mt 19:27 Then answered Peter and said unto him, Behold, we have forsaken all, and followed thee; what shall we have therefore?
28 And Jesus said unto them, Verily I say unto you, That ye which have followed me, in the regeneration when the Son of man shall sit in the throne of his glory, ye also shall sit upon twelve thrones, judging the twelve tribes of Israel.
There can be no doubt that the apostles to whom he was speaking in Matt 19 were Jews, and there is no doubt they were also the foundation of the church of Jesus Christ because the scriptures says this at a later date in Ephesians.
19 Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God;
20 And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner [stone];
21 In whom all the building fitly framed together groweth unto an holy temple in the Lord:
22 In whom ye also are builded together for an habitation of God through the Spirit.
1 For this cause I Paul, the prisoner of Jesus Christ for you Gentiles,
The context says the "ye" is referencing gentiles and is what the Ephesian congregation was made up of. The point is that while Jews and gentiles are one in Christ they are distinct in Christ as well. However the worldwide church as it is being built over the centuries is in view here and there are distinctively Jews and gentiles in it. It has a Jewish foundation.