ויקרא, פרק ז׳, פסוק י״ג

A thanksgiving offering presents a unique phenomenon within the Temple service, bringing together leavened bread and unleavened bread as part of a festive meal of gratitude for survival and miracles. At a basic level, these two types of baked goods are simply brought side by side [אבן עזרא, חזקוני, שטיינזלץ]. However, many commentators point out that the leavened bread is actually the primary element of the offering, while the unleavened breads serve merely as a secondary addition [מלבי״ם, תורה תמימה, הופמן].

The centrality of the leavened bread is evident in several ways. Quantitatively, the amount of fine flour allocated for the ten leavened loaves is equal to the amount used for all thirty unleavened loaves combined [תורה תמימה, מלבי״ם, ביאור יש״ר, הופמן, אדרת אליהו]. Conceptually, the very purpose of the thanksgiving offering is to publicize God's kindness to the masses. Achieving this requires a large feast with many participants. Leavened bread, which is tasty and far more suitable for a feast than unleavened bread—often defined as the bread of poverty—serves as the culinary centerpiece that attracts people to join the celebration [העמק דבר]. Symbolically, while the unleavened bread represents the elevated table of the Temple, the leavened bread symbolizes a person's daily sustenance, which they bring to express gratitude to God for maintaining their life [הופמן].

The physical preparation of the loaves follows exact guidelines. The baked goods do not become sanctified until they are completely baked and form a crust in the oven, transitioning entirely from the state of raw, round dough into finished, ready-to-eat food [מלבי״ם, תורה תמימה, פרדס יוסף].

The primary approach among commentators is that these loaves do not receive their holiness independently; rather, they are entirely dependent on the animal sacrifice. The breads are sanctified only at the exact moment the animal is slaughtered. Until that slaughter takes place, the bread can still be redeemed to secular status, and it is not invalidated if it is moved from its proper place or touched by someone who has immersed in a ritual bath that same day.

Furthermore, the slaughtering process must be done with explicit intent for a thanksgiving offering. Only through this specific, directed purpose does the bread achieve its sacred status [תורה תמימה, מלבי״ם, אדרת אליהו]. These foundational rules also extend to the peace offering brought by a nazirite on the day he completes his term and shaves his hair. That offering similarly requires accompanying breads and exact measurements of flour and oil, even though it does not include leavened bread [תורה תמימה, מלבי״ם, אדרת אליהו].