The Torah declares of a certain offender: "he shall be put to death." But the text does not specify the method of execution. The Mekhilta records a debate about which form of capital punishment applies — a question that carries enormous legal weight in rabbinic jurisprudence, where the Torah prescribes four distinct methods of execution: stoning, burning, the sword, and strangulation.
The initial assumption is death by the sword. But the Mekhilta immediately challenges this: perhaps the verse intends strangulation instead? How can we determine the correct method when the text itself is silent?
The resolution comes through a gezeirah shavah — a hermeneutical principle that links two verses sharing identical language. The phrase used here is "moth yumoth" — a doubled verbal form meaning "he shall surely die." This exact same phrase appears elsewhere in the Torah in connection with an adulterer, where the prescribed punishment is strangulation.
Since the Torah uses the identical expression "moth yumoth" in both cases, the sages concluded that the legal consequence must also be identical. Just as the adulterer is executed by strangulation, so too is the offender in this passage executed by strangulation. The shared language creates a legal bridge between the two verses, transferring the known penalty from one context to the unknown context of the other.
This method of interpretation — deriving law from verbal parallels rather than explicit statements — is one of the thirteen principles by which the Torah is expounded. Every repeated phrase in Scripture is a potential legal signal, connecting distant passages into a unified system of justice.