The grain offering is what the system provides for people and for occasions where an animal is not required, and it is not a lesser thing for that. Leviticus 2 gives it in four preparations: raw fine flour with oil poured over it and frankincense laid on top; cakes baked in an oven, unleavened and mixed with oil, or wafers spread with oil; a griddle preparation, broken up with oil poured over it; and a pan preparation. In each case the priest lifts a handful of the flour and oil with all of the frankincense and burns it as the memorial portion. The remainder belongs to Aaron and his sons and is eaten unleavened in a holy place.
Two things are excluded from the altar with it and the pairing is deliberate: no leaven and no honey may be burned, though both may be brought as a first fruits offering that does not go on the fire. Against those exclusions stands a positive requirement that reads as the general rule for the whole system: every offering is salted, and salt is called the salt of the covenant.
The grain offering is not only an alternative to an animal. A measure of fine flour with oil, together with a libation of wine, accompanies each animal offering of the public service, scaled to the size of the beast, so that most grain offered at the sanctuary arrived alongside meat rather than instead of it. One preparation is entirely burned: the offering a priest brings on his own behalf, of which no portion is eaten, on the principle that a priest may not be the beneficiary of his own offering.