Judaism

Judaism

Judaism is the religion of the Jewish people, who numbered about 14.8 million in 2020 by Pew Research Center's count. Its scriptures teach that one God made a covenant with Israel's ancestors and gave the Torah at Mount Sinai. Its best-known modern movements are Orthodox, Conservative, Reform, and Reconstructionist, and they differ on how Jewish law should be kept today.

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What is Judaism?

Judaism is the religion of the Jewish people, though Jews differ on whether being Jewish is mainly a matter of religion. In Pew's survey of Israel in 2014 and 2015, 70 percent of Haredi Jews said it is mainly religion, while 83 percent of secular Jews said it is mainly ancestry or culture. Haredi means strictly observant Orthodox; news reports often say ultra-Orthodox.1

Who counts as Jewish is debated too. The Orthodox Union holds that a Jew is the child of a Jewish mother or a convert. Its 2014 glossary entry reports that Reform and Conservative leaders say Israeli authorities have not recognized conversions by their rabbis.2 In March 2021 the Rabbinical Assembly reported that Israel's High Court had ruled Conservative and Reform conversions performed in Israel valid for the purposes of the Law of Return.3 In 1986 the Rabbinical Assembly, the Conservative rabbinate, reaffirmed descent through the mother as its standard.4 In 1983 the Central Conference of American Rabbis, the Reform rabbis' body in North America, presumed the child of one Jewish parent, mother or father, to be Jewish if raised as a Jew, through public acts of Jewish identification.5

Judaism's scripture is the Tanakh, also called the Hebrew Bible. In the Torah, its first part, God tells Israel at Mount Sinai: if ye will hearken unto My voice indeed, and keep My covenant, then ye shall be Mine own treasure from among all peoples (Exodus 19:5)6. A covenant is a binding agreement.

What do Jews believe?

Jewish teaching starts from one God: Deuteronomy 6:4 declares that the LORD is one.6 The philosopher Maimonides (1135 or 1138 to 1204 CE) listed thirteen principles he considered binding on every Jew, among them the divine origin of the Torah and a coming Messiah.78 Menachem Kellner calls it the first comprehensive account of Judaism's dogmas.9 The movements differ most on revelation and on Jewish law, called halakhah:

  • Orthodox. The Orthodox Union teaches that Moses received every word of the Torah from God, and Orthodox Jews hold that the oral law was revealed with it.1011
  • Conservative. The Rabbinical Assembly describes its approach as fidelity to inherited tradition and the courage to integrate necessary change12.12 Its thinkers hold a range of views on revelation.1314
  • Reform. Reform rabbis call the Torah God's ongoing revelation to our people and the record of our people's ongoing relationship with God15.15
  • Reconstructionist. Mordecai Kaplan, the founding thinker, described Judaism as the evolving religious civilization of the Jewish people16; Reconstructing Judaism today describes people as the agents of its change.16

The Beliefs page gives each movement's answers in full.

How did Judaism begin?

The Torah's account of Abraham, Moses, and Sinai and historians' reconstruction of ancient Israel differ.17 The History page gives both in full.

The tradition's account

In the Torah's account, God called Abram to leave his home for a land God would show him, and made a covenant with him and his descendants. It was to continue through Isaac, the son of Sarah.6 Later, in this account, God freed the Israelites from Egypt and gave the Torah at Sinai.6 Solomon began the Temple in the four hundred and eightieth year after the children of Israel were come out of the land of Egypt (1 Kings 6:1)6.6 The Mishnah traces a chain of teachers from Sinai: Moses received the Torah at Sinai and transmitted it to Joshua, Joshua to the elders, and the elders to the prophets18.18

The historians' view

The Yale scholar Christine Hayes writes that archaeologists have found no evidence of the extensive conquest and destruction that the book of Joshua describes. New hill-country villages of the thirteenth to eleventh centuries BCE are linked with early Israel.17 The archaeologist William Dever dates the Merneptah stele, an Egyptian inscription naming a people called Israel in Canaan, to about 1206 BCE, and finds no direct evidence for the Exodus.19

Carol Meyers suggests that a small group who had been in Egypt may have reached Canaan, and that their memory became the national narrative of all Israel.20 James Hoffmeier argues for the authenticity of the Exodus tradition.21 Scholars differ on how much of the early account is history; Hayes writes that most see the Exodus story as evidence for the presence of some escaped slaves.2217

What are the Tanakh and the Talmud?

The Tanakh takes its name from the first letters of its three parts: Torah (teaching), Neviim (the Prophets), and Ketuvim (the Writings).23 The Orthodox Union teaches that God gave the Torah to Moses word for word, spoke through the prophets, and inspired the Writings.10

In rabbinic tradition, the Oral Torah explains how the written commandments are kept, and the Mishnah is its first written collection. The Orthodox Union teaches that God gave the Oral Torah to Moses at Sinai.24 Judah ha-Nasi redacted the Mishnah around 200 CE.2526 The Talmud adds generations of rabbinic discussion. The Orthodox Union credits Rav Ashi and his colleagues with compiling the Babylonian Talmud, the version most often used, around 500 CE.27 Michael Swartz dates its redaction to the early sixth century CE, and Stephen Wald writes that it took shape over many centuries, before and after Rav Ashi.828 The Sacred Texts page covers how each was handed down.

How do Jews practice?

Shabbat, the Sabbath, comes every seventh day, a day on which the Ten Commandments forbid work.6 The Orthodox Union calls it a day of rest and delight, and Reform rabbis a call to holiness, rest, and joy.2915

The Orthodox Union describes Rosh Hashanah, the New Year, as a day of judgment marked by the blowing of the shofar, a ram's horn, and Yom Kippur, the Day of Atonement, as the holiest day of the year.3031 It presents Passover as recalling the Exodus, with the seder, a festive meal eaten in a set order; Shavuot as the giving of the Torah; and Sukkot as dwelling in a sukkah, a hut.32333435 The calendar's months follow the moon and its years the sun: a month is added in seven years of every nineteen, which, on one common explanation, keeps Passover in the spring season the Torah names.3637

In traditional practice, communal prayer takes place in the synagogue and requires a minyan, a quorum of ten. Swartz writes that the synagogue began primarily as a place for study and became the main place of worship after the Temple fell.8 Orthodox practice generally counts only men; the Encyclopaedia Judaica reports that early in the 21st century Reform, Reconstructionist, and most Conservative congregations counted women too.3839 The Practices page covers the Jewish year.

What are the main branches?

Judaism's best-known modern movements are Orthodox, which includes Modern Orthodox, Hasidic, and other Haredi communities; Conservative; Reform; and Reconstructionist.11 In Pew's 2020 survey of Jewish adults in the United States, 37 percent identified as Reform, 17 percent as Conservative, 9 percent as Orthodox, 4 percent with other movements, and 32 percent with none.40

In Pew's survey of Israeli Jews in 2014 and 2015, 9 percent were Haredi, 13 percent Dati (religious), 29 percent Masorti (traditional), and 49 percent Hiloni (secular).1 Ashkenazi, Sephardi, and Mizrahi Jews are heritage communities, not branches. The Branches page describes each movement.

How many Jews are there?

Pew counted about 14.8 million Jews in 2020.41 Outside Israel, Pew generally counts people who give Judaism as their religion, though in some countries it uses estimates by the demographer Sergio DellaPergola; in Israel it uses the government's register, which counts children of Jewish mothers and formal converts.42 DellaPergola also counts Jews who identify with no religion, and estimated 15,736,800 Jews on January 1, 2024.43

In 2020, by Pew's count, nearly half of Jews lived in Israel and about four in ten in the United States.42 The Today page has more. For a side-by-side look, see Christianity vs Judaism and the book Christianity vs Judaism.

Common questions

What do Jews believe?

Jewish teaching centers on one God, a covenant between God and the Jewish people, and the Torah, God's teaching. The movements read these differently. The Orthodox Union teaches that every word of the Torah came from God to Moses. Conservative Judaism holds to Jewish law while allowing for change, Reform Judaism calls the Torah God's ongoing revelation, and Reconstructionist Judaism describes Judaism as an evolving religious civilization. The Beliefs page has more.

When and where did Judaism begin?

The Torah traces Judaism to God's covenant with Abraham and to the giving of the Torah to Moses at Mount Sinai, after the Exodus from Egypt. The Yale scholar Christine Hayes links early Israel to villages in Canaan's hill country from the thirteenth century BCE, and the archaeologist William Dever dates an Egyptian inscription naming Israel there to about 1206 BCE. Scholars differ on how much of the earlier account is history. The History page gives both accounts.

What is the difference between the Torah and the Talmud?

The Torah, the five books of Moses, is the first part of the Tanakh, the Hebrew Bible. The Talmud records rabbinic discussion of the Mishnah, which rabbinic tradition holds is the first written collection of the Oral Torah. The Orthodox Union credits Rav Ashi and colleagues with compiling the Babylonian Talmud around 500 CE; Stephen Wald describes a process of centuries. Orthodox Judaism holds that the Oral Torah was given to Moses at Sinai. The Sacred Texts page has more.

What are the branches of Judaism?

The best-known modern movements are Orthodox, Conservative, Reform, and Reconstructionist, with smaller groups such as Humanistic Judaism. In the United States in 2020, Pew found 37 percent of Jewish adults Reform, 17 percent Conservative, 9 percent Orthodox, and 32 percent tied to no movement. Israeli Jews more often describe themselves as Haredi, religious, traditional, or secular. Ashkenazi, Sephardi, and Mizrahi are heritage communities, not branches. The Branches page describes each movement.

How many Jews are there in the world?

Pew Research Center counted about 14.8 million Jews in 2020, 0.2 percent of the world's population, generally counting by religion outside Israel. The demographer Sergio DellaPergola, who also counts Jews who identify with no religion, estimated 15,736,800 at the start of 2024. In 2020, by Pew's count, nearly half of Jews lived in Israel and about four in ten in the United States. The Today page explains why counts differ.

Who is considered Jewish?

Under Jewish law as Orthodox Judaism applies it, a Jew is the child of a Jewish mother or a convert; the Conservative rabbinate reaffirmed this in 1986. In 1983 North America's Reform rabbis (the Central Conference of American Rabbis) presumed a child of one Jewish parent to be Jewish if raised as a Jew, through public acts of identification. The Rabbinical Assembly reported in 2021 that Israel's High Court had ruled Conservative and Reform conversions valid for the Law of Return.

What is Shabbat?

Shabbat, the Sabbath, is the weekly day of rest. The Ten Commandments call the seventh day a sabbath on which no work is done. The Orthodox Union describes it as a day of rest and delight that recalls God's completion of creation. Reform Judaism's 1999 principles describe Shabbat as a call to holiness, rest, and joy. The Practices page covers Shabbat and the holy days.

Sources

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  3. Rabbinical Assembly. RA Celebrates Israel High Court Decision Affirming Conservative and Reform Conversions for the Law of Return. Rabbinical Assembly (the Conservative/Masorti rabbinic association), 2021. Accessed 2026-11-04.
  4. Joel Roth and Akiba Lubow (Committee on Jewish Law and Standards, The Rabbinical Assembly). A Standard of Rabbinic Practice Regarding Determination of Jewish Identity. The Rabbinical Assembly, 1986, p. 1. Accessed 2026-10-29.
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