The term "Torah" can also refer to the whole Hebrew Bible. Because some Jews consider the rules and customs passed down via oral traditions to be part of God's revelation to Moses and so comprise the "oral Torah," Torah is also believed to encompass both the oral law and the written law. In classical rabbinic literature, the terms "Oral Law" or "Oral Torah" are often used interchangeably with "Torah."
In Judaism, there is no distinction made between religious laws (or commandments) that were given to the Jewish people through Moses at Mount Sinai and later interpreted by the prophets and their disciples and those that were added by other authors over time. All of Israel's prophetic teachers continued to add new commands to the old ones, so the body of Jewish law is always growing rather than standing still.
According to Maimonides, Moses received all of God's commandments at one time or another but only recorded some of them. The rest was preserved by Joshua and the elders of Israel until Moses' death, at which point they were all compiled into a single book called the Pentateuch or Five Books of Moses.
The early Christians adopted many practices from Judaism including a belief in a single set of holy books (the Old Testament), a belief in a personal God and an afterlife, and a system of religious leaders known as "presbyters" who led worship and administered sacraments such as baptism.
The term "Torah" is frequently used to refer to the first five books of the Hebrew Bible (Old Testament), commonly known as the Law (or the Pentateuch, in Christianity). However, in Judaism the five books of the Torah are called the Olam Habah (incomplete creation) because they contain all that God wanted humans to know about him and life on earth before the world was to be destroyed at the flood. Thus, the Torah is not only the collection of laws but also a record of creation and history.
In Christian theology, the Old Testament is considered part of the Holy Scriptures, which constitute the true and full revelation of God's will for humanity. Christians believe that the New Testament expands on and completes what was said in the Old Testament.
In Islam, the holy book is called the Qur'an. It has been argued that the Torah and the Qur'an should be seen as two sides of the same coin: both are sacred texts that contain moral guidance for humanity.
Each of these three great religions has interpreted the other two's use of the term "Torah" (Law) incorrectly. The Jews view the Law as something added to the covenant that God made with their ancestors at Mount Sinai; it wasn't there already but rather something new that applied specifically to this generation of people.
Rabbinic Judaism considers the Oral Torah or Oral Law Hebrew: tvrh SHbl ph, Torah she-be-al peh, lit. The so-called "Written Torah" (Hebrew: tvrh SHbKHtb, Torah she-bi-khtav, lit. The "known to all") to be equally important as the Written Torah.
The importance of the Oral Torah is evident from the fact that the Sages established hundreds of rules and laws regarding its interpretation and application. In addition, many aspects of Jewish life are either based on interpretations of passages in the Oral Torah or prescribed by authorities who had unique access to events before them. These include matters such as prayer times, the order of blessings in prayer, the requirements for a minyan (a quorum for prayer), restrictions on contact with certain people, and more.
Texts of some significance in determining Jewish law include the Prophets, the Talmud, and the Midrash. Each of these categories of texts has many different versions or manuscripts that differ only slightly from one another. As long as these differences do not affect meaning, they are regarded as authoritative expressions of the original text.
In addition to these canonical sources, there are other texts which are cited as having authority by some Jews. For example, some Jews cite the works of medieval commentators, while others rely on their own understanding of Scripture.