Mishneh Torah, Leavened and Unleavened Bread 2

Sugya Map

• Issue: Defining the Torah-level obligation of tashbitu (destruction of leaven) and identifying the timeframe of the 14th of Nisan as the legislative mandate.
• Nafka Mina: Whether the mitzvah is fulfilled by mental nullification (bitul) alone vs. physical removal (bi’ur), and whether the obligation is triggered upon the arrival of the prohibition or precedes it as a preparatory requirement.
• Primary Sources: Exodus 12:15, Exodus 34:25, Pesachim 5a, Mishneh Torah, Leavened and Unleavened Bread 2:1.

Text Snapshot

Rambam opens: "It is a positive commandment from the Torah to destroy chametz before the time it becomes forbidden to be eaten... 'On the first day, destroy leaven from your homes' Exodus 12:15. On the basis of the oral tradition, it is derived that 'the first day' refers to the day of the fourteenth." The nuance in leshon ("destroy... before the time it becomes forbidden") signals that the mitzvah is not merely a result of the prohibition, but a proactive requirement to ensure a clean state prior to the cutoff.

Readings

Insight 1: The Sefer HaMenucha on the Nature of Bitul

The Sefer HaMenucha argues that while bitul (nullification in the heart) is indeed a Torah-level act, it lacks a beracha because it lacks ma’aseh (physical action). The chiddush here is the ontological status of the house: nullification works because it strips the chametz of its "Torah-identity" as property. Once nullified, the chametz is legally "dust." The Menucha insists that while bitul satisfies the Torah requirement of tashbitu, it is insufficient if one has the ability to physically remove the chametz—rendering the Rabbinic search a necessary "clarification" of the mental state.

Insight 2: Yitzchak Yeranen on the "Double" Proof

The Yitzchak Yeranen tackles the Kessef Mishneh’s frustration regarding Rambam’s reliance on two sources. If the Oral Tradition (Masorah) already defines "first day" as the 14th, why does Rambam invoke Exodus 34:25 ("Do not slaughter the blood of My sacrifice with chametz")? The Yitzchak Yeranen posits that the Oral Tradition provides the day, but the verse provides the hour (the onset of the seventh hour). He suggests that Rambam views the verse not as an independent derasha, but as a necessary anchor for the specific moment of the 14th when the obligation crystallizes, lest we rely on subjective logic (svara) instead of clear scriptural boundaries.

Friction

The strongest kushya concerns the intersection of Pesachim 5a and the Rambam. The Talmud asks: "If we know it is the 14th, why do we need a verse?" Rambam cites both tradition and the slaughter of the Pesach. The friction: Does the mitzvah of tashbitu begin at the moment of the prohibition (midday/the 7th hour) or earlier?

The Ra’avad (in his glosses) and the Rosh differ significantly from the Rambam. The Rosh argues that one does not fulfill the mitzvah if they destroy it before the prohibition starts; the mitzvah is intrinsically linked to the time of the issur. The terutz suggested by the Seder Mishnah is that Rambam holds the 14th is "dedicated" to this mitzvah. Thus, performing it at any point on the 14th—even early in the morning—is a fulfillment of the command to "destroy," as the day itself is the temporal vessel for the mitzvah. The Acharonim often align this with the Rambam’s view of "preparation as fulfillment."

Intertext

The interplay between the Pesach slaughter and chametz removal reflects a broader theme in the Mishneh Torah: the synchronization of sanctuary time and domestic time. Just as one cannot slaughter the Korban Pesach while chametz exists (Exodus 34:25), the domestic space must mirror the purity of the Temple. This parallels the logic found in Shulchan Aruch, Orach Chayim 431, where the prohibition of starting work or study is not merely a technicality but a recognition that the transition of the 14th demands total focus, similar to the "Shabbat of the Year" (the 7th year, see Leviticus 25:4).

Psak/Practice

In practice, the psak follows the Rambam’s heuristic: bitul is the Torah-level minimum, but the Rabbinic bedikah (search) is the standard of performance. The Mishnah Berurah clarifies that even if one relies on bitul, one must still physically search if they are aware of specific chametz. The meta-psak heuristic for the 14th is: Bitul handles the unknown, while Bedikah handles the reality. As we approach the month of Av (the month of Menachem Av), we are reminded that just as we clear the physical leaven, we engage in teshuva to clear the "leaven in the dough"—the pride that prevents us from realizing our potential.

Takeaway

The Rambam teaches that tashbitu is not merely an avoidance of a sin, but a proactive sanctification of the home through an act of intellectual and physical surrender. "Nullification of the heart" turns chametz into dust, but the candle of the search turns the house into a sanctuary.