What is the significance of the fact that our Lord never went to the dispersed of Israel? Was it that God did not consider the dispersed as part of Israel? I believe not, I believe that, in one sense, the term "Israel" includes all those born of Abraham, Isaac and Jacob. But many would say that the leaders of the nation of Israel, i.e. those in Jerusalem, spoke for the dispersed. So when the leaders at Jerusalem rejected Christ with the stoning of Stephen, those leaders spoke for all Israel. I would like to address that subject in this message.
In short, it is true that Christ never went to the dispersed of Israel during His EARTHLY ministry. But His ministry did not end with His death and resurrection. It continued throughout the Acts period. Just because our Lord was no longer on earth, does not mean that He no longer directed His disciples to accomplish His will. Let us consider God's EXPANDING ministry during the Gospel and Acts periods.
The nation, as represented by the chief men at Jerusalem rejected Christ when they had Him crucified. Then after His ascension Christ told Peter to wait in Jerusalem until Pentacost. The Word of God never records our Lord or any of His disciples preaching on Pentacost during the Gospel period. Why was Peter told to wait in Jerusalem until Pentacost? Pentacost was one of three feast in which, according to the Mosaic Law, all Jewish men were to gather at Jerusalem. All Jewish men included, of course, the dispersed from every nation, as recorded in Acts 2. So by telling Peter to wait in Jerusalem until Pentacost, God's ministry EXPANDED to the dispersed .
Then at Acts 7 when the leaders of the nation rejected Him, Christ called Saul to FURTHER EXPAND His minstry by going to the dispersed of Israel and even to the Gentiles.
The point is that Christ's ministry did not end with the end of the Gospel period. As His ministry continued it expanded to include all Israel and Gentiles in an effort to make Christ's return possible. So even though during His EARTHLY ministry Christ went only to the nation of Israel, His ministry continued from heaven through His disciples and expanded to include the dispersed and the Gentiles.
In short, It is only by limiting Christ's ministry to the Gospel period that one is led to the errouneous conclusion that Christ did not go to the dispersed of Israel.
I will add that the "chief men" at Rome represented the dispersed of Israel. It was when they rejected Paul's message in Acts 28 that Israel was set aside, not when the leaders of only part of Israel, i.e. those in Jerusalem, rejected Christ with the stoning of Stephen.