I don't understand this comment. What distinction are you talking about?
I would like to know what you are saying that Isa 49:22-23 is saying? At what time, even in the future, will Gentiles be servants to the Jews? Even in, what you call, the Millennial reign Gentile Christians will judge the 12 tribes of Israel. So when does this prophecy come about?
I am saying that those scriptures are speaking about the Church. In verse 2-8 the reference to Christ is unmistakeable. In verse 10 through the end of the chapter, he is speaking of the church where we see alignments to scriptures talking about the church in the New Testament. You see I don't have problem with these scriptures as I see the Church as Israel today.
As Gentile believers we were grafted into the olive tree, which in OT and NT scriptures, is Covenant Israel. Since being grafted in Paul tells us that we partake of the root(Christ) and the fatness of the olive tree. Therefore all of the promises and prophecies in the OT that were given to Israel now apply to the Church where, as you say, there is no distinction between the Jew and the Gentile.
GLJCA