The Rambam · Sefer Zemanim
הלכות חמץ ומצה ו׳Leavened and Unleavened Bread 6
Chapter 6 of 9 in Leavened and Unleavened Bread — 12 halachot
Halacha 1א׳
מִצְוַת עֲשֵׂה מִן הַתּוֹרָה לֶאֱכל מַצָּה בְּלֵיל חֲמִשָּׁה עָשָׂר שֶׁנֶּאֱמַר (שמות יב יח) "בָּעֶרֶב תֹּאכְלוּ מַצֹּת". בְּכָל מָקוֹם וּבְכָל זְמַן. וְלֹא תָּלָה אֲכִילָה זוֹ בְּקָרְבַּן הַפֶּסַח אֶלָּא זוֹ מִצְוָה בִּפְנֵי עַצְמָהּ וּמִצְוָתָהּ כָּל הַלַּיְלָה. אֲבָל בִּשְׁאָר הָרֶגֶל אֲכִילַת מַצָּה רְשׁוּת רָצָה אוֹכֵל מַצָּה רָצָה אוֹכֵל אֹרֶז אוֹ דֹּחַן אוֹ קְלָיוֹת אוֹ פֵּרוֹת. אֲבָל בְּלֵיל חֲמִשָּׁה עָשָׂר בִּלְבַד חוֹבָה. וּמִשֶּׁאָכַל כְּזַיִת יָצָא יְדֵי חוֹבָתוֹ:
The Torah commands us to eat matzah on the night preceding the fifteenth day of Nisan, as it is written: "In the evening, you shall eat unleavened bread" (Exodus 12:18), everywhere and throughout time. It did not make this eating dependent on the Passover sacrifice. Rather this is a commandment on its own; and [the time of] its commandment is all of the night. But during the rest of the festival, the eating of matsa is optional - if he wants, he may eat matsa; [and] if he wants, he may eat rice, millet, roasted grains or fruits [instead]. However on the night of the fifteenth alone, it is an obligation. By eating a piece of matzah the size of an olive [on the night of the fifteenth] one fulfills his duty.
Halacha 2ב׳
בָּלַע מַצָּה יָצָא. בָּלַע מָרוֹר לֹא יָצָא. בָּלַע מַצָּה וּמָרוֹר כְּאֶחָד יְדֵי מַצָּה יָצָא יְדֵי מָרוֹר לֹא יָצָא. שֶׁהַמָּרוֹר כִּטְפֵלָה לַמַּצָּה. כְּרָכָן בְּסִיב וְכַיּוֹצֵא בּוֹ וּבְלָעָן אַף יְדֵי מַצָּה לֹא יָצָא:
[If] one swallowed matsa, he has fulfilled [the obligation. If] he swallowed bitter herbs, he has not fulfilled [it. If] he swallowed matsa and bitter herbs like one (at the same time), he fulfilled matsa; he did not fulfill bitter herbs - as the bitter herbs are like [something] auxiliary to the matsa. [If] he wrapped them in [palm] bast or that which is similar to it and swallowed them, he did not even fulfill matsa.
Halacha 3ג׳
אָכַל מַצָּה בְּלֹא כַּוָּנָה כְּגוֹן שֶׁאֲנָסוּהוּ עַכּוּ"ם אוֹ לִסְטִים לֶאֱכֹל יָצָא יְדֵי חוֹבָתוֹ. אָכַל כְּזַיִת מַצָּה וְהוּא נִכְפֶּה בְּעֵת שְׁטוּתוֹ וְאַחַר כָּךְ נִתְרַפֵּא חַיָּב לֶאֱכל אַחַר שֶׁנִּתְרַפֵּא. לְפִי שֶׁאוֹתָהּ אֲכִילָה הָיְתָה בְּשָׁעָה שֶׁהָיָה פָּטוּר מִכָּל הַמִּצְוֹת:
[If] he ate matsa without intent - such as if idolaters or brigands forced him to eat [it] - he has fulfilled his obligation. [If] he was epileptic and ate a kazayit of matsa at the time of his seizure, and was healed afterwards - he is obligated to eat [it again] after he was healed. For the first eating was at a time when he was exempt from all of the commandments.
Mishneh Torah, Torat Emet 363 edition, via Sefaria — public domain
English: Sefaria Edition, tr. R. Francis Nataf, 2019 — CC BY
English: rendered from the Hebrew for this app — our own, not a borrowed translation