במדבר כ״ט:י״ז-י״ט

ומנחתם ונסכיהם לפרים. פָּרֵי הֶחָג שִׁבְעִים הֵם כְּנֶגֶד שִׁבְעִים אֻמּוֹת, וּמִתְמַעֲטִים וְהוֹלְכִים, סִימָן כְּלָיָה הִיא לָהֶם, וּבִימֵי הַמִּקְדָּשׁ הָיוּ מְגִנִּים עֲלֵיהֶם מִן הַיִּסּוּרִין (סוכה נ"ה):

Their meal-offerings and their libations for the bulls. There were seventy festival bulls, representing the seventy nations, which were progressively diminishing, symbolizing their destruction. During the time of the Sanctuary, [however,] These sacrifices shielded them from suffering.

ולכבשים. כְּנֶגֶד יִשְׂרָאֵל שֶׁנִּקְרְאוּ "שֶׂה פְזוּרָה" (ירמיהו נ'), וְהֵם קְבוּעִים, וּמִנְיָנָם תִּשְׁעִים וּשְׁמוֹנָה, לְכַלּוֹת מֵהֶם תִּשְׁעִים וּשְׁמוֹנֶה קְלָלוֹת שֶׁבְּמִשְׁנֵה תוֹרָה; בַּשֵּׁנִי נֶאֱמַר וְנִסְכֵּיהֶם עַל שְׁנֵי תְמִידֵי הַיּוֹם, וְלֹא שִׁנָּה הַלָּשׁוֹן אֶלָּא לִדְרֹשׁ, כְּמוֹ שֶׁאָמְרוּ רַבּוֹתֵינוּ זִ"לִ (ספרי; שבת ק"נ) בַּשֵּׁנִי וְנִסְכֵּיהֶם, בַּשִּׁשִּׁי וּנְסָכֶיהָ, בַּשְּׁבִיעִי כְּמִשְׁפָּטָם, מֵ"ם יוֹ"ד מֵ"ם הֲרֵי כָאן מַיִם, רֶמֶז לְנִסּוּךְ הַמַּיִם מִן הַתּוֹרָה בֶּחָג:

And the lambs. Representing Israel, which is called “the dispersed lamb.” Their numbers are constant, and they total ninety eight, to nullify the ninety eight curses in Mishneh Torah. On the second day, וְנִסְכֵּיהֶם, “and their libations,” is said, in relation to the day’s two constant-offerings. The change in language was intended for exposition, as the Rabbis, of blessed memory, remarked: On the second day, וְנִסְכֵּיהֶם, “and their libations,” is said, on the sixth, וּנְסָכֶיהָ, “and her libations,” on the seventh, כְּמִשְׁפָּטָם, “according to ‘their’ requirement.” מ"ם, יו"ד, מ"ם . which spells מַּיִם, “water,” and is an allusion that the water libation, during the Festival is Scriptural.