Judaism

Judaism is an Abrahamic, monotheistic, and ethnic religion that encompasses the spiritual, cultural, and legal traditions of the Jewish people. For religious Jews, it is the way they observe the Mosaic covenant—an agreement they believe was made between God and the Jewish people. It is recognized as one of the earliest monotheistic faiths. The religion and culture of Judaism are built on a wide range of texts, traditions, theologies, and worldviews. Its core scriptures include the Torah (meaning “Teaching”), the Nevi’im (“Prophets”), and the Ketuvim (“Writings”), which together form the Hebrew Bible. In Modern Hebrew, this collection is often called the Tanakh—an acronym of its three parts—or the Miqra (“that which is called out”). Beyond these scriptures, Jewish religious writings include the Oral Torah, which consists of the Mishnah, Talmud, Tosefta, and Jewish legal Midrashim (expositions). Other key categories are Halakha (Jewish law), Aggadah (narrative), and responsa. The word Torah specifically refers to the Five Books of Moses, but it can also mean the entire body of rabbinic literature and any teachings based on those texts, encompassing many interpretations. Judaism’s texts, traditions, and values strongly influenced later Abrahamic religions like Christianity and Islam, and through Christianity’s role in the West, Judaism has indirectly shaped Western culture. There are many Jewish religious movements, most of which come from Rabbinic Judaism. This tradition holds that God revealed his laws and commandments to Moses on Mount Sinai in both the Written Torah and the Oral Torah. Historically, groups such as the Sadducees, Hellenistic Jews of the Second Temple period, the Karaites, and some modern non-Orthodox denominations have challenged parts of this claim. Some modern branches, like Humanistic Judaism, may be secular or nontheistic. Today, the largest movements are Orthodox Judaism (including Haredi and Modern Orthodox), Conservative Judaism, and Reform Judaism. Their main differences lie in how they approach Halakha, rabbinic authority, rabbinic literature, and the significance of the State of Israel. Orthodox Judaism sees the Torah and Halakha as divinely given, eternal, and unchangeable, and insists on strict observance. Conservative and Reform Judaism are more liberal, with Conservative Judaism generally taking a more traditionalist stance than Reform Judaism. A typical Reform view is that Halakha should serve as general guidance rather than binding obligations. Historically, rabbinical courts called batei din enforced Halakha; these still exist, but Jewish practice is now mostly voluntary. No single person or organization holds ultimate authority over theology or law; instead, authority lies in the Jewish texts and the rabbis and scholars who interpret them. Jews are an ethnoreligious group, including those born Jewish and those who convert. In 2025, the global Jewish population was estimated at 14.8 million, though levels of religious observance vary widely, from strict to none at all. The word “Judaism” comes from the Latin *Iudaismus*, itself from the Ancient Greek *Ioudaismos*, which derives from the verb meaning “to side with or imitate the Judeans.” Its ultimate source is the Hebrew name “Yehudah” (Judah), son of Jacob, and the namesake of the tribe, region, and Kingdom of Judah. The term *Ioudaismos* first appears in the Koine Greek book of 2 Maccabees in the 2nd century BCE. In that context, it meant “seeking or forming part of a cultural entity,” and was the opposite of *Hellenismos*, which meant submission to Hellenistic culture. The conflict between these two ideas drove the Maccabean Revolt, giving rise to the term. Rabbi Shaye J. D. Cohen argues that *Ioudaïsmós* should be translated as “Judaeanness” rather than “Judaism,” since it originally referred to all characteristics that made Judeans Judean, not just religious beliefs. Daniel R. Schwartz, however, contends that in the Maccabean books, the term refers specifically to religion, reflecting the ideological divide between Pharisees and Sadducees, as well as pro- and anti-Hasmonean factions.