Negative commandment · Lo Ta’aseh #189 of 613
Not to eat bread made from newly grown produce before Pesach
שלא לאכול פת תבואה חדשה קודם הפסח
The verse · Vayikra 23:14
וְלֶחֶם וְקָלִי וְכַרְמֶל לֹא תֹאכְלוּ עַד־עֶצֶם הַיּוֹם הַזֶּה עַד הֲבִיאֲכֶם אֶת־קׇרְבַּן אֱלֹהֵיכֶם חֻקַּת עוֹלָם לְדֹרֹתֵיכֶם בְּכֹל מֹשְׁבֹתֵיכֶם
“And you shall eat neither bread, nor parched corn, nor green ears, until that very day, until you have brought an offering to your God: it shall be a statute for ever throughout your generations in all your dwellings.”
The Rambam’s words
Not to eat bread made from newly grown produce before Pesach, as [Leviticus 23:14] states: "[Until that day,...] you may not eat bread..."
שלא לאכול פת תבואה חדשה קודם הפסח, שנאמר "ולחם . . . לא תאכלו" (ויקרא כג,יד).
Why · Sefer HaChinuch #303
To not eat from the new grain before the end of the sixteenth of Nissan
“It is from the roots of the commandment [that it is] since the main nourishment of the creatures is from grains. And therefore it is fitting to offer from them a sacrifice to G-d Who gave them, before the creatures benefit from them.”
Who & when
“And this prohibition is practiced in every place and at all times — whether in the presence of the [Temple] (when it exists) or not in the presence of the [Temple] — by males and females.”
Where in the Mishneh Torah
Hilchot Forbidden Foods הלכות מאכלות אסורות