- Theism, a term that usually refers to the belief in a 'personal' god, that is, a single god with a distinctive personality, rather than just a divine force.
- Deism is a form of monotheism in which it is believed that one god exists. However, a deist rejects the idea that this god intervenes in the world. Hence any notion of special revelation is impossible, and the nature of god can only be known through reason and observation from nature. A deist thus rejects the miraculous, and the claim to knowledge made for religious groups and texts.
- Monistic Theism is the type of monotheism found in Hinduism. Such type of theism is different from the Semitic religions as it encompasses panentheism, monism, and at the same time includes the concept of a personal god as an universal, omnipotent supreme being.
- Pantheism holds that the Universe itself is God. The existence of a transcendent supreme extraneous to nature is denied. Depending on how this is understood, such a view may be presented as tantamount to atheism, deism or theism.
- Panentheism is a form of theism that holds that god contains, but is not identical to, the Universe. The universe is part of god. This is also the view of Process theology and also Hinduism. According to Hinduism, the universe is part of God but God is not equal to the universe but in fact transcends it as well. However, unlike Process theology, God in Hinduism is omnipotent. Panentheism is thought of as "God is within the universe as the soul is within the body". By some accounts, panentheism is also called monistic theism in Hinduism. But since process theology is also included in the broad definition of panenetheism and does not accept an omnipotent supreme being, the Hindu view would be called monistic theism.
- Substance monotheism, found e.g. in some indigenous African religions, holds that the many gods are different forms of a single underlying substance, and that this underlying substance is God. This view has some similarities to the Christian trinitarian view of three persons sharing one nature.
In contrast, see Polytheism, which holds that there are many gods. Dualism teaches that there are two independent divine beings or eternal principles, the one good, and the other evil, as set forth especially in Zoroastrianism, but more fully in its later offshoots in Gnostic systems, such as Manichaeism.
Most monotheists would say that, by definition, monotheism is incompatible with polytheism. However, devotees within polytheistic religious traditions often behave like monotheists. This is because a belief in multiple gods does not imply the worship of multiple gods. Historically, many polytheists believe in the existence of many gods, but worship only one, considered by the devotee to be the supreme god. This practice is termed henotheism. There are also monotheistic theologies in Hinduism which teach that the many forms of God, i.e., Vishnu, Shiva, or Devi merely represent aspects of a single or underlying divine power or Brahman (see articles on Nirguna Brahman and Saguna Brahman). Some claim that Hinduism never taught polytheism .
Worship of a single god within a pantheon and the abolition of all others may be monotheism, as in the case of the Aten cult in the reign of the Egyptian pharaoh Akhenaten, under the wifely influence of the Eastern-originating Nefertiti. Iconoclasm during this pharaoh's rule is considered a chief origin for Abrahamic destruction of idols, holding no other God before the preferred deity(dually and subtly acknowledging the existence of the other gods, but only as foes to be destroyed for their drawing of attention away from the prime objective; mono-deity). The monotheism as inherited by the Hyksos in Exodus by Moses, is supposed to be an inheritance of Akhenaten's religious policies, as they were formerly polytheist like the Egyptians. Other issues like the Divine Right of Kings also stems from pharaohic laws on the ruler being the demigod or representative of the Creator on Earth. The massive tombs in the Egyptian pyramids which aligned with astronomical observations, exemplifies this relationship between the pharaoh and the heavens and was subsequently adopted by Christian royalty by claiming a direct lease on ruling by God.
Zoroastrianism is considered by some to be the earliest monotheistic belief to have evolved among humanity, though it is not fully so, as the chief god Ahura Mazda is not the sole creator. It has been theorized that Judaism was influenced by Zoroastrianism as well as by Greek philosophy before arriving at its modern monotheistic view of God. Earlier Judaism is assumed to have claimed only that YHVH was a tribal deity who was the patron of the descendants of Abraham, or that there were many gods but that theirs was the most powerful. This view is not compatible with the modern self-understanding of the Abrahamic religions – Judaism, Christianity, Islam – which traditionally insist that exclusive monotheism is the original religion of all mankind, all other gods being viewed as idols and creatures which wrongly came to be worshipped as deities.
Several professors of archaeology have made the controversial claim that many stories in the Hebrew Bible/Old Testament, including important chronicles about Moses, Solomon, and others, were actually initially developed by scribes employed by King Josiah (7th century BCE) to rationalize monotheistic belief in YHVH. This theory observes that the neighbouring countries, such as Egypt, Persia etc, although keeping written records, have no writings about the stories of the Bible or its main characters before 650 BCE. Such claims are detailed in Who Were the Early Israelites? by William G. Dever, William B. Eerdmans Publishing Co., Grand Rapids, MI (2003). Another such book is The Bible Unearthed by Neil A. Silberman and colleagues, Simon and Schuster, New York (2001).
Although Christians believe in one god, they profess that this god is, in fact, three persons: God the Father, God the Son, and God the Holy Spirit (collectively called the Trinity), Christians insist that their faith is monotheistic. Typically, Christian theology holds that these three persons are not independent bur are 'homoousios', that is sharing the same essence or substance of divinity. However, some have suggested that Christianity is a form of Tritheism. Moreover, some minority sects of Christianity, such as the Jehovah's Witnesses, deny the idea of Trinity, while others, such as some sects of Mormonism, worship only one god, but are open to the existence of others. Rastafarians, like many Christians, hold that God is both a unity and a trinity, in their case God being Haile Selassie. Rastas see themselves and possibly all individuals, as the Holy Spirit element of the Trinity, with Haile Selassie as both God the Father and God the Son. Haile selassie is also seen as the head, and the Rastafarians of the body.
Monotheism can be divided into different types on the basis of its attitude to polytheism: inclusive monotheism claims that all polytheistic deities are just different names for the single monotheistic God; exclusive monotheism claims that these deities are distinct from the monotheistic God, and false (either invented, or demonic, in nature.)
In Hinduism views are broad and range from monism, dualism, pantheism, panentheism, alternatively called monistic theism by some scholars, and strict monotheism, but are not polytheistic as outsiders perceive the religion to be. Hinduism has often been confused to be polytheistic as many of Hinduism's adherents are monists, and view multiple manifestations of the one God or source of being. Hindu monists see one unity, with the personal Gods, different aspects of only One Supreme Being, like a single beam of light separated into colours by a prism, and are valid to worship. Some of the Hindu aspects of God include Devi, Vishnu, Ganesh, and Siva. Additionally, like Judaeo-Christian religions which believe in angels, Hindus also believe in less powerful entities, such as devas.
Contemporary Hinduism is now divided into four major divisions, Vaishnavism, Shaivism, Shaktism, and Smartism. Just as Jews, Christians, and Muslims all believe in one God but differ in their conceptions of him, Hindus all believe in one God but differ in their conceptions. The two primary form of differences are between the two monotheistic religions of Vaishnavism which conceives God as Vishnu and Shaivism, which conceives God as Shiva. Other aspects of God are in fact aspects of Vishnu or Shiva; see Smartism for more information.