Negative commandment · Lo Ta’aseh #99 of 613
Not to offer a sacrifice which is unsalted
שלא להקריב תפל
The verse · Vayikra 2:13
וְכׇל־קׇרְבַּן מִנְחָתְךָ בַּמֶּלַח תִּמְלָח וְלֹא תַשְׁבִּית מֶלַח בְּרִית אֱלֹהֶיךָ מֵעַל מִנְחָתֶךָ עַל כׇּל־קׇרְבָּנְךָ תַּקְרִיב מֶלַח
“And thy every meal offering shalt thou season with salt; nor shalt thou suffer the salt of the covenant of thy God to be lacking from thy meal offering: with all thy offerings thou shalt offer salt.”
The Rambam’s words
Not to offer a sacrifice which is unsalted, as [Leviticus 2:13] states: "Do not omit the salt of G-d's covenant."
שלא להקריב תפל, שנאמר "ולא תשבית מלח ברית אלוהיך" (ויקרא ב,יג).
Who & when
“And [it] is practiced at the time of the [Temple] by the males of the priesthood, as it is for them to complete the requirements of the sacrifice.”
Where in the Mishneh Torah
Hilchot Things Forbidden on the Altar הלכות איסורי המזבח