The Torah itself establishes salt as the sign of an eternal covenant with God: Vayikra 2:13 commands that every meal-offering be salted and declares it "the salt of your God's covenant," while Bamidbar 18:19 describes the priestly portions as "an everlasting covenant of salt before God" — language whose permanence Targum Jonathan on Bamidbar reinforces by rendering the covenant as one that, like salt that seasons sacrificial flesh, "shall never be annulled" (Targum Jonathan on Bamidbar 18:19).
Rashi traces this covenantal status to Creation itself, explaining that a promise was made to the lower waters at the six days of Creation that they would be brought to the altar through salt and through the water-libation of Sukkot (Rashi on Vayikra 2:13), a reading that Tur HaArokh (Vayikra 2:13) transmits in his name as well.
The Gemara in Menachot 20a derives from the juxtaposition of "an everlasting covenant of salt" (Bamidbar 18:19) with "the covenant of an everlasting priesthood" (Bamidbar 25:13) that just as a sacrifice cannot be offered without the priesthood, it cannot be offered without salt — making salting an indispensable rite — and Menachot 21a further clarifies through close reading of Vayikra 2:13 that the obligation requires actual solid salt (not salt-water), with the preferred variety being salt of Sodom.
Among the medieval commentators, the Ramban (Vayikra 2:13) offers a philosophical reading: salt is formed from water by the power of the sun yet destroys the very fertility that water creates, embodying within itself opposing forces — water and fire, life and destruction — and the covenant symbolized by salt therefore encompasses the full range of divine attributes and governance; the Kli Yakar (Vayikra 2:13) develops this further, arguing that salt, which contains both the power of fire and the nature of water and corresponds according to the Kabbalists to the attributes of divine justice and mercy, is called "the covenant of your God" precisely because bringing it on the altar is an act of accepting God's sovereignty over all opposites in creation.
Gur Aryeh (Vayikra 2:13) adds that both salt and the water-libation were chosen for the altar together because they represent genuine opposites — salt is dry while water is moist — and their simultaneous presence on the altar expresses a hidden dimension of the sacrificial rite that he notes is deeply embedded in midrashic tradition; similarly, רש"ר הירש, ויקרא, וראה שם עוד emphasizes that salt is not merely called the "salt of a covenant" but is itself described as the covenant — a substance that gives flavor to food yet also permanently prevents growth, making it a fitting symbol of an unconditional and indestructible bond.
The salt-covenant extends beyond the Temple to the Shabbat table: Shulchan Arukh, Orach Chayim 167:5 rules in the Rema's gloss that it is a mitzvah to place salt on every table before breaking bread, because the table is likened to the altar and eating to a sacrifice, based on the verse "on all your offerings you shall offer salt," and that salt protects from calamity; Mishnah Berurah 167:30 adds that a midrashic tradition holds that when Israel waits at table without yet performing a mitzvah the Accuser finds an opening to prosecute, and the covenant of salt shields them — and the Mekubalim therefore prescribed dipping the Hamotzi slice into salt three times.
The Zohar, as explained by Sulam on Zohar, Vayechi 666, asks why salt is so significant and answers that it purifies and sweetens what is bitter, giving it taste — a mystical dimension that Likkutei Torah, Vayikra 4:1 echoes in Hasidic teaching: salt itself has no taste of its own, yet it draws out and sweetens the flavor of meat, analogous to a higher spiritual force that activates potential lying dormant in what it touches.
The Gemara in Berakhot 34a extends the salt metaphor into the realm of character and conduct, comparing a prayer leader who accepts the role without any hesitation to a dish with no salt — tasteless — while one who refuses excessively is like a dish ruined by too much salt, illustrating how deeply the image of salt as the proper measure of flavor was woven into rabbinic moral discourse.
On the practical halachic plane, Shulchan Arukh, Yoreh De'ah 69:1 codifies the requirement to salt meat thoroughly in order to draw out its blood and render it permissible, a process rooted in the Talmudic ruling recorded in Chulin; and Tzitz Eliezer (9:35) rules that the fundamental importance of salt in this context lies in the explicit ruling of the Sages — derived from Chulin 113a and accepted by all authorities — that meat cannot be released from its blood except through thorough salting, and that the intent of all authorities is specifically actual salt.
אלשיך, מלכים ב ב כ observes that the sea of Kinneret, whose waters are sweet, is compared to holiness, while the Salt Sea is compared to impurity — suggesting that salt in the Torah carries a dual symbolic valence, capable of representing both the preserving, sanctifying force of the covenant and, in its excessive or destructive form, the opposite pole.
