Monotheism

Monotheism is the belief in only one god, rather than the two (dualism) or more (polytheism) as in Ancient Greece, Ancient Rome and Ancient Egypt.

Many religions are monotheistic, such as Judaism, Christianity, Islam, Baha'i Faith, Sikhism, Eckankar, Zoroastrianism, Cao Dai and Tenrikyo. Some pagan and neo-pagan religions are also monotheistic.

Deism is the belief that a higher being like god exists but not many gods, revelation, religions, rituals, sacred books (like the Bible or Quran), prophets (like Jesus or Muhammad), etc.

Judaism and Zoroastrianism are thought to be the oldest living monotheistic religions.

• Stanford Encyclopedia of Philosophy

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