The peace offering creates a unique partnership connecting the altar, the person bringing the offering, and the priests. As part of this shared experience, the priests are granted two choice cuts of meat. The process of designating these portions involves specific symbolic movements: a horizontal motion of bringing forward and drawing back, and a vertical motion of raising and lowering [רש״י, ברכת אשר]. These physical actions are intended to ward off harmful winds and damaging dews [גור אריה]. On a deeper conceptual level, the horizontal movement represents the act of giving to the priest and to humanity, while the vertical lifting signifies absolute dedication to God in heaven [רד צ הופמן].
Although in later generations both cuts of meat were moved horizontally and vertically together, they retain distinct titles that trace back to the dedication of the Tabernacle. During those inaugural days, only the breast portion was moved horizontally by itself and given to Moses, whereas the thigh was burned on the altar alongside the fats as an elevated offering to God. Even after both cuts became standard gifts to the priests, their original names were preserved to commemorate the historical moment when the priests first acquired them [שד״ל, מלבי״ם, ברכת אשר, רד צ הופמן].
The allocation of these portions reflects a profound historical shift. Before the sin of the Golden Calf, these select cuts rightfully belonged to the Israelites themselves. However, following that failure, the privilege was removed from the nation, with God taking the portions and transferring them to the priests [תורה תמימה, פענח רזא, צפנת פענח, אדרת אליהו]. This clarifies the true nature of the transaction. The individual bringing the offering is not handing a personal present to the priest. Because these cuts were originally destined for the altar, God is essentially taking them from His own table to grant them to the priests, meaning the priests are sustained directly by the divine table [ביאור יש״ר, ביאור שטיינזלץ].
This arrangement is highly specific. Only these exact portions from the sacred offerings are designated for the priests, and this rule cannot be used as a precedent for other priestly gifts that involve ordinary, non-sacred meat [תורה תמימה, מלבי״ם]. Furthermore, the distribution establishes a clear hierarchy, dictating that the High Priest takes precedence over the regular priests when receiving these parts [רלב״ג].
To solidify this arrangement, it is established as a permanent law. This prevents a misconception that if the Israelites were to fully repent and regain the pristine spiritual standing they held before the Golden Calf, the portions would revert to them. Unlike human gifts, which are subject to change or cancellation, God's grant is permanent, securing the priests' rights for all time [תורה תמימה, פענח רזא, אדרת אליהו, פרדס יוסף]. Yet, while the initial transfer of ownership was an absolute divine decree, the actual physical handover must be handled respectfully. Despite possessing a legal right to the meat, the priests are forbidden from seizing these portions by force. They must receive them through the goodwill, consent, and willing participation of the Israelites [מלבי״ם, רש ר הירש, אדרת אליהו].