There will be no mingling in his children, of the mixture of conversions, and thus: ‘there is no receiving of proselytes in the messianic age’.lxxxivBT’Avodah Zarah 3b, Yevamot 24b. For upon the seed of Jacob it is stated: (Ps. 80:9) You brought out a vine from Egypt... Just as the vine does not accept grafting from any other species, so have his seed been guarding the sign of the covenant, and they do not accept grafting from any other species.
And all who guard the sign of the covenant are worthy of royalty,