שמות טז ,כה : א כְלֻּהוּ הַיוֹם כּ י־שַבָת הַיוֹם לַה' הַיוֹם לֹא ת מְצָאֻּהוּ בַשָדֶה
The Sforno notes that the word הַיוֹם (today) appears three times in this Pasuk to teach us three things:
- Although the entire amount of Mahn was in one’s hands from the eve of Shabbos it should not be consumed at once but appropriated for specific meals.
- Although the food prepared of the eve of Shabbos can be used the entire day of Shabbos but not the next day.
- This order is to be followed every week on the Shabbos.