Khordeh Avesta (Khordeh Avesta Bā-Māyeni). The oldest Zoroastrian religious scripture, as preserved at present, is known as the Avesta. A section of this Avesta is known as the “Khordeh-Avesta’ which means the “Smaller or Selected Avesta”. This is the book of daily prayers of the Zoroastrians. It is a cherished possession of every devoted Zoroastrian household. The Khordeh Avesta is a collection of prayers selected from other major works of extant Avesta literature such as Yasna, Vispered, Vendidad, and the Yasht Literature.
Zoroastrians recite their prayers in Avesta which is a sacred language. Among several words for “prayers” in Avesta, one is called “mānthra”, which means “thought (force), word, the holy word”. It is similar to the Sanskrit “mantra”, and the Sanskrit translation is rendered as “mānthravāni” which is also significantly called “ādesha”: “Divine Command”. You might also be interested in the Zend Avesta: Link.
Download the Khordeh Avesta PDF here (365 pages/3.2MB):