I guess so. They can graft in to the Chosen People and adhere to Gods Law or not. That's pretty straight forward.
Rev. 22:14,15 "14 Blessed are they that do his Commandments, that they may have right to the Tree of Life, and may enter in through the gates into the City.
15 For outside are dogs, and sorcerers, and fornicators, and murderers, and idolaters, and whosoever loves and makes a lie.
Do you mean by that post that among the Gentiles only those who keep the Jewish Sabbath and obey all the Laws of Moses will enter the kingdom of heaven ?