When the Lord brings back those who have been in exile (wherever a Jewish person is, if not in Israel is considered to be in exile), the nations will rejoice at the goodness of God.
Isaiah 49: 9b-12, 19-21: “They shall feed along the roads, and their pastures shall be on all desolate heights. They shall neither hunger nor thirst, neither heat nor sun shall strike them; for He who has mercy on them will lead them, even by the springs of water He will guide them.
“I will make each of My mountains a road, and My highways shall be elevated.
“Surely these shall come from afar; Look! Those from the north and the west, and these from the land of Sinim.”
Sing, O heavens! Be joyful, O earth! And break out in singing, O mountains! For the Lord has comforted His people, and will have mercy on His afflicted.
“For your waste and desolate places, and the land of your destruction, will even now be too small for the inhabitants; and those who swallowed you up will be far away. The children you will have, after you have lost the others, will say again in your ears, ‘The place is too small for me; give me a place where I may dwell.’”
Then you will say in your heart, ‘Who has begotten these for me, since I have lost my children and am desolate, a captive, and wandering to and fro? And who has brought these up? There I was, left alone; but these, where were they?’”