The Talmuds are systematic commentaries on the Mishnah, the law code of Judaism formulated in the late second century CE. Two Talmuds developed, one in the land of Israel ca. 400 CE, the other in Babylonia, between ca. 500 and 600 CE. The Palestinian Talmud comments on the divisions of the Mishnah that concern Agriculture, Appointed Times, Women (family law and personal status), and Damages, but it ignored Holy Things. The Babylonian Talmud covers Appointed Times, Women, Damges, and Holy Things (Temple Law) but omits reference to Agriculture. Neither Talmud deals with Purities, excluding the tractate Niddah, on the woman's menstrual period. The first Talmud stresses Mishnah exegesis, with 90 percent of its volume devoted to that task. The second Talmud is not continuous with the first, although it does follow a shared program of exegesis of the Mishnah. In addition to Mishnah exegesis, the Babylonian Talmud devotes substantial attention to the explanation of blocks of biblical materials. In Mishnah exegesis both Talmuds take up words and phrases, the biblical sources of the Mishnah's laws, contradictions in cases and rules that require harmonizations, and similar problems. They engage in speculation on principles behind case laws of the Mishnah and bring into harmony diverse cases that present contradictions in the application of those unifying principles. The Babylonian Talmud differs from the Palestinian in one important respect. In the Palestinian Talmud the fundamental editorial structure derives solely from the Mishnah, but in the Babylonian Talmud, not only the Mishnah but also long passages of scripture serve to organize and unify discourse.
The Talmuds fill vast gaps in the Mishnah's discourse. They account for the authority of the MIshnah by systematically linking its rules and laws to scripture. The need to explain the standing and origin of the Mishnah led sages to posit, first, that God's revelation of the Torah at Sinai encompassed the Mishnah as much as scripture, and second, that the Mishnah was handed on through oral formulation and oral transmission from Sinai to the framers of the document as we have it. Consequently, the two Talmuds, along with a variety of other books of exegesis of the Mishnah and of scripture, came to be called the oral Torah. The twin explanations for the status of the Mishnah first surfaced in the Palestinian Talmud, which contains clear allusions to the dual Torah, one part in writing, the other, oral, and now in the Mishnah.
The two Talmuds make use of further documents that fall into the classification of (oral) Torah. They cite and regularly explain the Tosefta, a collection of supplements to the laws of the Mishnah. The Tosefta presents materials of three types: citation and gloss of a passage of the Mishnah; amplification of a Mishnah passage not cited verbatim; and a small amount of material essentially unrelated to the Mishnah. The Talmuds further know commentaries to the written Torah by sages of the time, such as Sifra to Leviticus, Sifre to Numbers, another Sifre, this one to Deuteronomy, Genesis Rabbah, Leviticus Rabbah, and the like. All of these other documents, but especially the Mishnah and its two great Talmuds, contain the teachings of the sages of late antiquity, from the first through the sixth centuries CE. The final statement of the whole is in the Talmud of Babylonia, the encyclopedia of Judaism that from the sixth century CE to the present has provided the focus for authoritative opinion.