I believe this is the prophecies of Eze 36:27 where God said that, "I will put My Spirit within you (which I believe may be the last surviving Jews), and cause you to walk in My statutes, and ye shall keep My judgments, and do
them."
This could be the final "new covenant" with the Jewish nation prophesied in Jer 31:31, which will not be the previous Torah but similar to it (v 32) concerning the type of covenant, in that it will be law-centric containing "statutes" and "judgments" (Eze 36:37).
The truths of the Eze/Jer prophecies are so obscure concerning Israel's end-time position that many have erroneously devised doctrines to attempt to explain these prophecies (even going back as far as the Church Fathers). There is no place in pure doctrine that ever substitutes the Church for Israel without also spiritualizing it to the point of drifting from the moorings of the massive evidence of Jewish language whenever the nation of Israel is mentioned in Scripture (with a single possible exception in
Gal 6:16 which may be inclusive to mean all Jews who believe in Christ). Fortunately, these prophecies, like many Biblical doctrines are nonessential in reating to receiving salvation.