The hymns of zoroaster preserved as part of the Avesta, are short poems, comparable to those of the Rig-Veda in India. Although their language is fairly intelligible, being closely akin to Vedic Sanskrit, their style and contents make them excessively difficult to understand and translate. Their burden is the praise, untiringly repeated and varied, of the god Ahura Mazda and of his court or family of Entities, who bear abstract names and are, at the same time, human (moral and social) qualities
personified. On the other hand, the cult of the ancient gods or daevas (cf. Sanskrit deva "god") and of the Evil Spirit [see ahura mazda (ohrmazd) and ahriman] and his entourage is unrelentingly combatted. It is not clear whether the sacrifice of the sacred liquor (see avesta) and the bull sacrifice were prohibited as such, or only special, repulsive forms of them. Anyhow, a destiny of woe in a dark hell with nauseous food is promised to the daevas-worshipers, whereas the followers of Ahura Mazda and his Holy Spirit, i.e., all those who rally to Truth, Justice, etc., against the forces of evil, will hereafter enjoy bliss, either in heaven or on a renovated earth. This renovation, entailing a resurrection of the body, will be brought about by coming saviors.
Bibliography: j. duchesne-guillemin, The Hymns of Zarathustra, tr. m. henning (London 1952); La Religion de l'Iran ancien (Paris 1962).
"Gāthās." New Catholic Encyclopedia. . Encyclopedia.com. (October 17, 2018). http://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/gathas
"Gāthās." New Catholic Encyclopedia. . Retrieved October 17, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/encyclopedias-almanacs-transcripts-and-maps/gathas