The integration into the fate and into the destiny of the chosen nation/people cannot be separated from the experience of belonging to knesset yisrael as an integrated whole whose historical existence embodies the dual ideas of loving-kindness and holiness. The Covenant of Sinai completed the Covenant of Egypt. Destiny joined fate; together they became a distinct covenantal unit. It is impossible to separate these constituent parts and formulate an outlook that opposes the unity of a nation of loving-kindness to that of a sanctified people. A Jew who participates in the suffering of his nation and its fate, but does not join in its destiny, which is expressed in a life of Torah and mitzvot, destroys the essence of Judaism and injures his own uniqueness. By the same token, a Jew who is observant but does not feel the hurt of the nation, and who attempts to distance himself from Jewish fate, desecrates his Jewishness.20
A gentile who wishes to join the nation must take upon himself both covenants. He places himself in the ambit of Jewish fate and sanctifies himself for the acceptance of the Jewish destiny. The act of conversion involves associating oneself as a member of the people of the Covenants of Egypt and of Sinai. Keep this important principle in mind: there is no such thing as partial conversion. One cannot omit one iota of either of these two Covenants. Total devotion to the Jewish people — as a nation that God took to Himself in Egypt, with all its tribulations, suffering, responsibilities, and actions; and as a holy people that is itself consecrated, heart and soul, to the God of Israel and His halakhic and moral demands — is the absolute foundation of Judaism and hence is also the basis of conversion.
For this reason, halakhah dictates that a convert who has been circumcised but has not yet immersed himself in a mikveh, or who has immersed himself and has not yet been circumcised, is not fully converted until he does both. Circumcision, which was given to Abraham the Hebrew, the father of Jewish fate, and which was fulfilled in Egypt prior to the offering of the Paschal sacrifice — the symbol of the redemption from Egypt — signifies the fateful otherness of the nation, its necessary isolation and uniqueness. Circumcision is a sign sculpted into the very physical being of the Jew. It is a constant, indelible sign between the God of the Jews and His people, one that cannot be erased. If the Covenant of Fate is not sealed in the flesh, then the singularity of peoplehood is absent and the gentile remains outside the bounds of the Covenant of Egypt.
Immersion in a mikveh, in contrast to circumcision, represents the integration of man into his great destiny and his entry into the Covenant of Sinai. The Jews were commanded to immerse themselves prior to the giving of the Torah at Sinai.21 Immersion purifies and elevates from the profane to the holy, from life as it is to a life filled with a sublime vision. When the convert emerges from the waters of the mikveh, a new spiritual reality replete with destiny fills him, and he is endowed with the sanctity of the Jew (kedushat yisrael). It is not coincidental that the act of accepting the yoke of the commandments is tied to immersion.22 The entire essence of immersion is the re-creation of the experience of the acceptance of the Torah and the elevation of the people to the status of a holy nation through its freely given commitment to obey God’s word. If the convert is circumcised and does not immerse himself, then the association of man to destiny is missing, and the gentile is fenced off from the Covenant of Sinai and from a halakhic identification with a holy nation.
The formula for conversion in the Book of Ruth contains these two aspects, and their essence lies in the four final words of Ruth to Naomi: “Your people shall be my people, and your God my God” (Ruth 1:16, emphasis added).