Zoroastrianism, the smallest of the world's great religions, is also one of the oldest. Founded more than 3,000 years ago by the prophet Zarathustra, it flourished in ancient Persia during the time of the Persian Empire. Scholars have long acknowledged the contributions of Zoroastrianism to other faiths, including Judaism, Christianity, Islam, and Buddhism. Concepts such as the notion of one God, heaven and hell, the dualism of good and evil, a savior to come, and everlasting life can trace their roots to the religion of Zarathustra. ""Zoroastrianism, Third Edition"" traces the history and beliefs of Zoroastrianism and its followers' determination through centuries of persecution and hardship into the present day. The Iranian and Indian Zoroastrian communities in which the religion has thrived without missionary efforts or vast numbers of believers is also explored. The coverage includes: the message of the prophet Zarathustra; the sacred fire; Zoroastrianism throughout history; the Zoroastrian scripture, the Avesta; rituals, beliefs, and rites of passage; and, traditional versus updated Zoroastrianism.

The youngest of the world religions, the Baha'i faith is also one of the fastest growing, increasing from 200,000 followers worldwide in 1950 to more than five million members today. Founded in 1863, this religion's essential belief centers on the unity of all religions and the abolition of racial, class, and religious prejudices. ""Baha'i Faith, Third Edition"" explores all aspects of the Baha'i faith, from the original teachings of its founder, Baha'u'llah, to the modern-day communities that exist in 236 countries and territories throughout the world. Coverage includes: ""Al-Kitab al-Aqdas"" (""The Most Holy Book of Baha'u'llah""); the roots and spread of the Baha'i faith; beliefs and teachings; worship and rites of passage; and the future of the Baha'i faith.