This is false. There is no 'spiritual Israel' distinctive within the Calvinist paradigm. It may be a common belief among Calvinists but it is not a distinctive of Calvinist doctrine. Even if it were, it wouldn't prove it false, by the way. That's the reason "guilt by association" is a logical fallacy.
Covenant theology (also known as Covenantalism, Federal theology, or Federalism) is a Calvinist conceptual overview and interpretive framework for understanding the overall flow of the Bible. It uses the theological concept of a covenant as an organizing principle for Christian theology. The standard form of covenant theology views the history of God's dealings with mankind, from Creation to Fall to Redemption to Consummation, under the framework of three overarching theological covenants: of redemption, works, and grace.
These three covenants are called theological because, though not explicitly presented as such in the Bible, they are thought of as theologically implicit, describing and summarizing the wealth of Scriptural data. Historical Reformed systems of thought treat covenant theology not merely as a point of doctrine or as a central dogma, but as the structure by which the biblical text organizes itself.
As a framework for biblical interpretation, covenant theology stands in contrast to dispensationalism in regard to the relationship between the Old Covenant (with national Israel) and the New Covenant (with the house of Israel (Jeremiah 31:31) in Christ's blood). That such a framework exists appears at least feasible, since from New Testament times the Bible of Israel has been known as the Old Testament (i.e., Covenant; see 2 Cor 3:14 [NRSV], "they [Jews] hear the reading of the old covenant"), in contrast to the Christian addition which has become known as the New Testament (or Covenant). Detractors of covenant theology often refer to it as "supersessionism"[citation needed] or as "replacement theology"[citation needed], due to the perception that it teaches that God has abandoned the promises made to the Jews and has replaced the Jews with Christians as his chosen people on the earth. Covenant theologians deny that God has abandoned his promises to Israel, but see the fulfillment of the promises to Israel in the person and the work of the Messiah, Jesus of Nazareth, who established the church in organic continuity with Israel, not as a separate replacement entity. Many covenant theologians have also seen a distinct future promise of gracious restoration for unregenerate Israel. - per wikipedia as a neutral source
Jews are not required to keep the Law today. Today there is no Jew or Gentile.
Perhaps you should familiarize yourself with what Dispensationalism teaches before freaking out so badly, proposing wild conspiracy theories and such.
Many of the thousand-plus people who attended Revive 2013, a religious conference held at the Dallas Sheraton last June, wear tzitzit. Many keep kosher and observe the Sabbath and Jewish holidays. Some of the men have beards and peyos. Some have even undergone adult circumcision and/or have circumcised their children. They learn Hebrew, Chumash, even Talmud, and travel whenever they can to Israel. All of them truly, deeply love Hashem.
Yet I’m fairly certain I was the only Jewish person there. Revive is an annual gathering for followers of Hebrew Roots, a movement of—for lack of a better term—Torah-observant gentiles. These are non-Jews who have no intention of converting to Judaism yet follow laws, customs, beliefs, and practices commonly associated with Judaism. And while they do believe that Jesus Christ is the son of God and the messiah—though in these circles he goes exclusively by his Hebrew name, Yeshua—they are emphatically not Christian. They do not celebrate Christmas or Easter. They do celebrate Passover and Sukkot. They do not display, either in their homes or as jewelry, crosses or other traditional Christian symbols. They do, however, wear Stars of David and post mezuzahs on their doors.
The movement’s central belief is that the Torah is still binding—that God, or Yahweh, or Hashem, did not intend for Yeshua’s appearance to render irrelevant the lessons of the Old Testament, whose rules and instructions remain valid. The Brit Chadasha, or New Testament, which most Christians believe superseded the Torah, is understood as a sort of extension of the Torah. Followers of Hebrew Roots believe that Christian practice has been, over the last two millennia, corrupted by pagan influences and like to say that they’re aiming for a pure, first-century version of their religion. In other words, they want to understand and observe the Torah the way they believe their messiah Yeshua did. Words like “restoration,” “revive,” “roots,” and “renew” are used a lot.
It’s impossible to quantify the number of Hebrew Roots followers worldwide, though I was given a range of estimates that ran from 200,000 to 300,000, most of whom have joined in the past 15 years. But the movement’s theology and praxis vary from ministry to ministry and person to person; what, exactly, Hebrew Roots is is still being worked out. Right now it encompasses a diverse swath of congregations and ministries with diverse beliefs and practices. What you’re supposed to do, when you’re supposed to do it, what you’re not allowed to do—these are the sorts of issues followers and ministries are beginning to consider. On some level, these questions are about religious identity: How “Jewish” do they want to be? Or, put another way, how un-Christian? source - Tablet magazine 2014