What is a deity? Now, that’s a good question. But it’s not one with a simple answer. In fact, there are several answers that we can give.
If your educational background is anything like mine, then at some point in your schooling you learned the basics of Greek mythology. The colorful stories of Zeus, Hera, Aphrodite, Poseidon, and the other gods worshiped in ancient Greece were some of my favorite things to read about. And while the Greeks eventually learned that no divine beings lived on Mount Olympus, the stories of the Greek gods became a core element of Western culture. This continues today, with movies, television shows, and even comic books retelling, adapting, and using these stories in various ways.
Though the Greek gods themselves are fictional, they fall under one of the definitions of the term deity. As Merriam-Webster tells us, one meaning of the word deity is “a god or goddess,” that is, a being who is worshiped—or in the case of the Greek gods, was worshiped—by people. (There are some modern pagans who would claim to worship the Greek gods or the gods of other mythologies, although the eclectic nature of modern paganism means that a lot of these worshipers do not necessarily believe these gods actually exist. In other words, it’s complicated.) Under this definition, a deity is usually a supernatural being, a being who belongs to a realm above or beyond what we normally experience with our five senses, though such deities, nevertheless, often interact with the world in which we live. A deity in this sense is also typically part of a pantheon of deities, other gods also worshiped by people, in a polytheistic religion—a religion that worships many gods. And each of these deities is typically associated with an element of nature. There will be a god or goddess of the sky, of the sea, of the harvest, of love, and so forth. Most ancient peoples practiced a polytheistic religion, and one can read about the gods of the ancient Egyptians, Celts, Norsemen, Romans, Babylonians, and various other groups. Polytheism also continues today in many cultures. Hinduism is arguably a polytheistic religion. The Church of Jesus Christ of Latter-day Saints affirms that many gods exist. Modern paganism often worships many gods, and various tribal religions around the world continue to worship many deities.
The label monotheistic deities might be a bit odd. After all, monotheism means “belief in one god.” Polytheistic faiths often believe that each nation or culture has its own set of gods, that these gods exist, and that no one group of these gods must be worshiped by all peoples (the Greeks worship the Greek gods, the Babylonians worship the Babylonian gods, the practitioner of one form of Wicca worships one set of Wiccan deities while a practitioner of a different form of Wicca worships another set of Wiccan gods, etc.). A monotheistic faith, however, believes that there is only one god, and most monotheistic faiths confess that this god must be worshiped by all people.
In this sense, we can use another definition of the word deity found in Merriam-Webster: the God, or the one Supreme Being. This is Deity with a capital “D.” The great monotheistic faiths of the world such as Christianity, Judaism, and Islam all claim that the God they worship is the only Deity, the one Supreme Being who created the universe and who alone is to be worshiped.
However, this section is titled Monotheistic Deities because while each of these faiths—and other varieties of monotheism—professes to worship the one and only God, the understanding of who God is differs greatly between them. Christians worship the Holy Trinity—Father, Son, and Holy Spirit, one God in three persons. Judaism and Islam do not worship the triune God. Islam worships the monadic deity Allah, whose final revelation came through Muhammad. Modern Judaism, which rejects Jesus as the Messiah, worships the monadic deity Yahweh.