Monotheism can be simply defined as the belief that there is only one god. While today’s largest religions, Christianity and Islam, are both monotheistic, it has not always the case that most people subscribed to a belief that there is only one god. Ancient men and women often believed in many gods, in some cases they had a god for just about anything that could happen, or not happen. A point of contention in religious debate is which religion is the oldest, or the original, monotheistic religion? Christianity lays claim to the title as it is an extension of Judaism, but Zoroastrianism claims the same title. The importance of this title is no small matter as the first monotheistic religion can state the later religions copied from them and are thus not the one true belief.
Around the twelfth century BCE, a man named Zoroaster lived in a small village in Persia. One day he received a vision from Ahura Mazda in which it was revealed to him that how the world was made, the true status of all the gods people worshipped and the true meaning, or form, of evil. Zoroaster went on to teach first his family, then his village, and ultimately his king, that all of the gods they worshipped were nothing but spiritual beings and demons. They were not in fact gods, the only true god was Ahura Mazda and his nemesis, though not a god, was Angra Mainyu (Dhalla).
Today Zoroastrianism is a modestly sized religion, counting fewer than 200,000 members with most of them living in India. In ancient times Zoroastrianism first gained significant prominence with the Persian king Darius during the fifth century BCE. Through the Persian empire, the religion spread across the middle east and up as far north as at least Macedonia and spread into parts of China as well (Zoroastrianism). It was the largest religion in the Middle East until the seventh century CE when it was violently pushed out by Islam.
Where Zoroastrianism is clear in that it was monotheistic from the beginning, Judaism is not so easy to handle. Judaism teaches a very similar belief, there is only one god, God or Yahweh, and he created the world and everything in it, including his nemesis Lucifer, who is a fallen angel, not a god. However, in the book of Numbers, there is a story of the Hebrew worshiping Baal of Peor, so while the religion may have been monotheistic, it appears the people practicing it were not always (Jewish Virtual Library).
While Judaism can trace itself back to the eighteenth century BCE with the life of Abraham, the Bible also contains numerous mentionings of the Hebrews worshiping gods other...