What is Judaism? Beliefs, texts and practice, explained

Judaism is the religion of the Jewish people: belief in one God who made a covenant, a binding agreement, with the people of Israel, and a way of life drawn from the Torah and centuries of rabbinic interpretation of it. It is one of the oldest living monotheistic religions, and being Jewish is a matter of belonging to a people as well as of belief.

In short

• Jews believe in one God, and that God's covenant with Abraham and the Torah given at Sinai bind the Jewish people to a life of commandments.
• The Hebrew Bible is the written core, but Judaism as practiced today is shaped by the rabbis' interpretation of it, gathered in the Mishnah and the Talmud.
• Judaism puts more weight on practice, on what a person does on the Sabbath, at the table and through the year, than on a fixed creed.

What do Jews believe?

At the center is one God, stated in the line Jews say morning and evening, the Shema: "Hear, O Israel: the Lord is our God, the Lord is one" (Deuteronomy 6:4). God is the creator of the world, acts in history and cares how people treat one another. The Hebrew Bible tells how God made a covenant with Abraham, and later, after leading his descendants out of slavery in Egypt, gave Moses the Torah at Mount Sinai. In Jewish belief the covenant is a relationship with duties on both sides: God's faithfulness, and Israel's keeping of the commandments.

The rabbis counted 613 commandments (mitzvot) in the Torah, from "love your neighbor as yourself" to rules on food, festivals and fair trade. The body of Jewish law built on them is called halakha, "the way to walk." Many beliefs are held more loosely than in some other religions. The philosopher Maimonides, in the 12th century, set out 13 principles of faith, among them God's unity, the truth of prophecy, a messiah to come and the resurrection of the dead. They became widely recited, but Jews have always argued about them, and Judaism has no single authority that defines orthodoxy for everyone.

Jewish identity is also a matter of peoplehood. In traditional Jewish law, a Jew is someone born to a Jewish mother or who converts. That is why people speak of secular Jews: someone can be fully Jewish while not believing in God. A Pew Research Center survey found that in 2020 about 5.8 million American adults were Jewish, and that many described their Jewishness mainly in terms of ancestry and culture (Pew Research Center).

What are the Torah and the Talmud?

The Torah, in the narrow sense, is the five books of Moses, from Genesis to Deuteronomy, read aloud in the synagogue from a handwritten scroll over the course of a year. In the wider sense the word means all Jewish teaching. The Hebrew Bible as a whole is called the Tanakh, an acronym for its three parts: Torah (teaching), Nevi'im (prophets) and Ketuvim (writings). It holds the same books as the Protestant Old Testament, ordered differently.

Rabbinic Judaism holds that Moses also received an Oral Torah, the explanation of how the written commandments are to be lived. Around 200 CE, Rabbi Judah the Prince gathered it into the Mishnah. Over the next three centuries, scholars in the land of Israel and in Babylonia discussed the Mishnah line by line, and those discussions became the Talmud. The Babylonian Talmud, completed around 500 to 600 CE, runs to thousands of pages, mostly argument: it often records the minority opinion next to the ruling, which is why studying Judaism means studying a debate.

How did Judaism take the shape it has today?

The religion most Jews practice today is rabbinic Judaism, which took shape after the Temple in Jerusalem was destroyed. The timeline below runs from the biblical kingdoms to the rabbis. Early dates rest partly on the Bible's own account, which historians weigh against archaeology.

When	What happened
c. 1000 BCE	A kingdom of Israel under David and Solomon, according to the Bible; Solomon builds the First Temple
722 BCE	Assyria conquers the northern kingdom of Israel
587/586 BCE	Babylon destroys Jerusalem and the First Temple; many are taken into exile
539–515 BCE	The Persian king Cyrus lets exiles return; the Second Temple is completed
70 CE	Rome destroys the Second Temple after a revolt
c. 200 CE	The Mishnah is compiled
c. 500–600 CE	The Babylonian Talmud is completed

The destruction of 70 CE, at the hands of the Roman Empire, was the turning point. With no Temple and no sacrifices, prayer, study and the keeping of the commandments took their place, and the synagogue and the home became the centers of Jewish life. After the exile, Jews lived for two centuries under Persian kings, some of whom honored Ahura Mazda, the God of Zoroastrianism, a contact scholars still discuss.

What does Jewish practice look like, week by week?

The weekly Sabbath, Shabbat, is the heart of Jewish practice. It runs from sundown on Friday to nightfall on Saturday, following the biblical day, which begins in the evening. Here is how a traditional Shabbat goes:

1. Friday, before sunset. Food is cooked in advance. Two candles are lit to mark the start.
2. Friday evening. A service at the synagogue, then a family meal that begins with kiddush, a blessing over wine, and a blessing over two loaves of braided bread, challah.
3. Saturday morning. The main service, with that week's portion of the Torah read from the scroll.
4. Through the day. Observant Jews refrain from 39 categories of creative work listed in the Mishnah, which today they apply to writing, cooking, driving and switching on electrical devices. The day is for rest, family, study and walking to synagogue.
5. Saturday night. Once three stars are visible, a short ceremony, havdalah, with wine, spices and a braided candle, separates the holy day from the week.

The year has its own rhythm, set by a calendar of lunar months adjusted to the solar year. Rosh Hashanah, the new year, and Yom Kippur, the Day of Atonement, a 25-hour fast on the tenth day of the new year, fall in early autumn. Passover retells the exodus from Egypt at a ritual meal, the seder, in spring. Sukkot, the autumn harvest festival, and Shavuot, which marks the giving of the Torah, complete the three ancient pilgrimage festivals. Hanukkah and Purim are smaller and later in origin, though Hanukkah has grown in prominence. Daily life has its practices too: the dietary laws of kashrut (keeping kosher), daily prayer, and rites of passage such as circumcision for boys and the bar or bat mitzvah at 13 or 12.

What are the main movements of Judaism today?

Modern Judaism divides less over belief than over how binding Jewish law is and who decides how it changes. The split began in 19th-century Germany, when Reform Judaism adapted worship to modern life.

Movement	Jewish law (halakha)	In practice	Share of US Jews, 2020
Orthodox	Binding, as interpreted by rabbinic tradition	Strict Shabbat and kashrut; men and women sit apart in prayer; includes Modern Orthodox and Haredi (including Hasidic) groups	9%
Conservative (Masorti)	Binding, but able to develop over time	Most congregations egalitarian; driving to synagogue on Shabbat permitted	17%
Reform	Guidance, with personal choice; ethics comes first	Services partly in the local language; women rabbis since 1972; in the US, accepts descent through either parent with a Jewish upbringing	37%
Reconstructionist and others	Judaism as the evolving civilization of a people	Small, progressive; includes Humanistic Judaism, which does not center God	about 4%
No particular movement	—	Practice varies widely	32%

The percentages are for American Jews in Pew's 2020 survey. In Israel the picture differs: most synagogues there are Orthodox, though most Israeli Jews are not (My Jewish Learning), and nearly all Israeli Jews describe themselves as Haredi, religious, traditional or secular rather than by these movements (Pew Research Center, 2016).

How many Jews are there, and how does Judaism relate to other faiths?

Pew Research Center counted about 14.8 million Jews in the world in 2020, about 0.2% of the world's population, most of them in Israel and the United States (Pew Research Center, 2025). The number is still below its level before the Holocaust, in which the Nazis murdered 6 million Jews.

Judaism is the oldest of the three religions that trace themselves to Abraham. Christianity began as a movement within first-century Judaism and took the Hebrew Bible as its Old Testament. Islam honors Abraham, Moses and the prophets of Israel as its own. How scholars place Judaism among the world's religions, and why the word religion fits a people awkwardly, is the subject of what religion is.

Check yourself

• Why can someone be Jewish without believing in God?
• What is the difference between the written Torah and the Talmud, and why does the Talmud record arguments it doesn't follow?
• What changed in Jewish practice after 70 CE, and why?

Sources

• Jewish Americans in 2020 — Pew Research Center, 2021
• How the Global Religious Landscape Changed From 2010 to 2020 — Pew Research Center, 2025
• The Jewish Denominations — My Jewish Learning
• Israel's Religiously Divided Society — Pew Research Center, 2016
• Judaism — Wikipedia