במדבר, פרק ט״ו, פסוק ד׳

When an individual brings an animal sacrifice, the ritual is not complete with the animal alone. It must be paired with a plant-based offering consisting of flour, oil, and wine. Even if the animal is brought as a completely voluntary gift, the accompanying grain and liquid offerings are a strict obligation [רש״ר הירש, שפתי חכמים, מזרחי]. This requirement applies universally to men and women alike, and even to someone who finds a lost animal and offers it [צפנת פענח, מלבי״ם]. Furthermore, unlike the wood and salt used on the altar, which are provided from public funds, these accompanying elements must be purchased entirely from the individual's private resources [העמק דבר].

There is a discussion among commentators regarding when this specific commandment took effect. While the daily communal sacrifices required these accompanying liquid and grain elements throughout the forty years in the desert, there is a disagreement over whether individual voluntary offerings required them during the desert wandering or only after entering the Land of Israel [ביאור יש״ר, הדר זקנים]. The required ingredients include finely ground wheat flour, measured as a tenth of an ephah, which is a standard dry volume measure [ביאור שטיינזלץ]. This flour is mixed with oil, measured as a quarter of a hin, equaling three logs [רלב״ג, ביאור שטיינזלץ]. From these specifications, commentators derive a fundamental rule: anyone wishing to volunteer an independent grain offering cannot bring less than one tenth of an ephah of flour and one log of oil [צפנת פענח, חזקוני, מלבי״ם].

A mathematical shift appears in the ratio of flour to oil depending on the size of the animal. While a sheep requires three logs of oil for one tenth of an ephah of flour, larger animals require proportionally less oil per measure of flour. Some explain this practically, noting that physically mixing a larger quantity of flour does not require an exact proportional doubling of the oil [הטור הארוך]. Others explain that three logs represent the absolute minimum amount a person can pledge for an independent oil or wine offering, and God aligned the measures for these accompanying elements accordingly [אור החיים]. Because the instructions begin with these smaller measurements, it is understood that this specific ratio applies to the smallest sacrificial animal, the sheep [רלב״ג].

The preparation and presentation of this accompanying offering differ significantly from standard grain offerings. The oil must be thoroughly mixed into the flour, while the wine is kept separate and not mixed in [מלבי״ם]. Additionally, whereas a standard independent grain offering only has a small handful burned on the altar while the priests eat the remainder, the grain offering that accompanies an animal is burned entirely on the altar [רש״י, שפתי חכמים, ברכת אשר על התורה, ביאור יש״ר]. The accompanying wine is also handled uniquely. Instead of being poured directly onto the altar's fire, it is poured into special perforated silver bowls resting on top of the altar. From there, the wine flows down through the perforations into deep cavities built into the altar's foundations [רש״י, שפתי חכמים, מזרחי, גור אריה].