Why does the Torah change here to "ve'NiskeiheM" from "ve'Niskah" on the other days, to "u'Nesachehah" on the sixth day, and on the seventh, from "ka'Mishpat" to "ke'MishpataM"?
Rashi (in Pasuk 18): The three extra letters spell 'Mayim' ? a hint to the Nisuch ha'Mayim ceremony, which began on the second day. 1
And was performed on six days, until the seventh day of Succos. See Torah Temimsh, note 20, who discusses the reason for Nisuch ha'Mayim.
QUESTIONS ON RASHI
Rashi writes that "ve'Niskeihem?" hints to Nisuch ha'Mayim is only on the sixth day. Why did the Torah not write it explicitly, like it wrote Nisuch ha'Yayin?
Moshav Zekenim: Nisuch ha'Yayin costs money, so the Torah needed to explicitly teach it. Nisuch ha'Mayim does not cost money, so a hint suffices.
