Sifra: The Thirteen Hermeneutical Rules of Rabbi Ishmael

Greco-Roman Period
Rabbi Ishmael, who lived in the first half of the second century, compiled a list of hermeneutical rules which govern the legal interpretation of the Torah. Modern scholars have noted the resemblance of some of these rules to the interpretive principles in use in the Greek world. These principles and their application are responsible for much of the halakhic Midrash in Rabbinic texts.

Rabbi Ishmael says- There are thirteen rules by means of which the Torah is
interpreted-

1. Inference is drawn from a less important premise to a more important premise, or
vice versa.

2. From the similarity of words or phrases in separate texts it is inferred that the law
expressed in the one must also be applied to the other.

3. A comprehensive principle, as contained in one or two biblical laws, is applicable to
all related laws.

4. When a generalization is followed by specification, the specification applies instead
of the generalization.

5. When a specification is followed by a generalization, the generalization then applies.

6. If a generalization is followed by a specification and then treated again by a general
term, one must interpret according to what the specification implies.

7. When, however, the specification or generalization is necessary for the sake of
clarity, rules 4 and 5 do not apply.

8. Whatever is first implied in a generalization and afterwards specified to provide new
information concerning it, is stated not only for its own sake, but to teach something
additional concerning the general proposition.

9. Whatever is first implied in a general law and afterwards specified to prove another
similar provision, is specified in order to alleviate, and not to increase the severity of that
provision.

10. Whatever is first implied in a general law and is afterwards specified to prove
another provision which is not similar to the general law, is specified in order to alleviate
the severity in some respects, but to increase it in other respects.

11. Whatever is first implied in a general law and is afterwards specified to determine a
new matter, cannot be applied to the general proposition, unless the text expressly states
that it can.

12. An ambiguous word or passage may be interpreted from its context or from a
subsequent expression in the text.

13. Similarly, when two biblical texts contradict each other, they can be reconciled only
by a third text.

108. Interpretive translation by Hadassah Schiffman Levy, based on P. Birnbaum, Daily Prayer Book (New
York- Hebrew Publishing, 1949), pp. 42-6.