"And flesh in the field, treifah" — the Torah declares that an animal torn by a predator in the field is forbidden to eat. But the Mekhilta asks: does this apply only in the field, or also inside the house?
(Leviticus 22:8) provides the answer: "Neveilah and treifah he shall not eat." This verse equates treifah (torn meat) with neveilah (carrion). The comparison is instructive. Just as neveilah is forbidden everywhere — in the field and in the house — so treifah is forbidden everywhere.
If treifah is forbidden everywhere, why does the Torah specify "in the field"? The Mekhilta answers: because Scripture speaks of the common instance. Animals are most commonly torn by predators in the field — in open, unprotected areas where wild beasts roam. The Torah uses the typical scenario without intending to limit the law to that scenario alone.
This principle — "Scripture speaks of the common instance" — appears throughout the Mekhilta as a way of reconciling specific language with universal rules. The Torah's mention of a particular location, time, or circumstance is often descriptive rather than restrictive. It tells you where the situation most frequently occurs, not where it exclusively occurs. The field is where torn animals are usually found. But a torn animal found in a barn is just as forbidden as one found in an open pasture. The prohibition follows the animal's status, not its location.