Zoroastrianism.
Zoroastrianism is a small religion with about 140,000 members. The religion was founded by Zarathushtra (Zoroaster in Greek). Conservative Zoroastrians believe that their religion was founded around 6000 BCE; other followers estimate 600 BCE. Historians and religious scholars generally date his life sometime between 1500 and 1000 BCE because of his style of writing. .
Zarathushtra lived in Persia, modern day Iran. Legends say that his birth was predicted and that attempts were made by the forces of evil to kill him as a child. He was condemned because of his monotheistic teachings in an area that was traditionally polytheistic. He was attacked for his teaching, but finally won the support of the king. Zoroastrianism became the state religion of various Persian empires, until the 7th Century. When Islamic Arabs invaded Persia in 650 AD, a small number of Zoroastrians fled to India where most are concentrated today. Those who remained behind have survived centuries of persecution, and reside mainly in Iran. The 1991 census counted 3,190 Zoroastrians in Canada.
The Zoroastrian holy book is called the Avesta. This includes the original words of their founder Zarathushtra, preserved in a series of five hymns, called the Gathas. The Gathas represent the core text of the religion. The Gathas are sacred poetry directed towards the worship of the One God, understanding of righteousness and cosmic order, promotion of social justice, and individual choice between good and evil.
Zoroastrians believe in a single god, Ahura Mazda, who is supreme. Communication between God and humans is by a number of Attributes, called Amesha Spentas or Bounteous Immortals. Within the Gathas, the original Zoroastrian sacred text, these Immortals are sometimes described as concepts, and are sometimes personified. One of the Zoroastrian schools of thought is also a concept of good and evil between the God, Ahura Mazda, and the evil spirit, Angra Mainyu.