Zoroastrianism is the world's oldest monotheistic religion. It was founded by Zoroaster in ancient Iran, approximately 3500 years ago, and served as its national religion for many centuries. In Zoroastrianism, the creator Ahura Mazda is all good, and no evil originates from him. Thus, in Zoroastrianism good and evil have distinct sources, with evil trying to destroy the creation of Mazda, and good trying to sustain it. The victory of good over evil is possible by upholding, through free will, the most basic tenets of the religion, which are Good Thoughts, Good Words, Good Deeds.