The Gathas (Gāθās) are the most sacred of the texts of the Zoroastrian faith, and are traditionally believed to have been composed by Zarathushtra (Zoroaster) himself.
The 17 hymns of the Gathas consist of 238 verses, of about 1300 lines or 6000 words in total. They were later incorporated into the 72-chapter Yasna (chapter: ha or had, from the Avestan ha'iti, 'cut'), which in turn is the primary liturgical collection of texts within the greater compendium of the Avesta. The 17 hymns are identified by their chapter numbers in the Yasna, and are divided into five major sections:
| 28-34 | Ahunavaiti Gatha | 'Sovereign Lord', 100 stanzas, (3 verses, 7+9 syllable meter) | ||
| 43-46 | Ushtavaiti Gatha | 'Radiant Happiness', 66 stanzas (5 verses, 4+7 syllable meter) | ||
| 47-50 | Spenta Mainyu Gatha | 'Positive Emanation', 41 stanzas (4 verses, 4+7 syllable meter) | ||
| 51 | Vohu Khshathra Gatha | 'Good Kingdom', 22 stanzas (3 verses, 7+7 syllable meter) | ||
| 53 | Vahishto Ishti Gatha | 'Spiritual Wisdom', 9 stanzas (4 verses, two of 7+5/two of 7+5+5 syllables) |
With the exception of Ahunavaiti Gatha, which is named after the Ahuna Vairya prayer (Yasna 27, not in the Gathas), the names of the Gathas reflect the first word(s) of the first hymn within them.
The sequential order of the Gathas is structurally interrupted by the Yasna Haptanghāiti ("seven-chapter Yasna", chapters 35-42), which is almost as old as the Gathas.
It must be noted that the Gathas are in an otherwise unknown language. The dependancy on Vedic Sanskrit is a significant weakness in the interpretation of the Gathas, as the two languages, though from a common origin, had developed independently. Sassanid era translations and commentaries (the Zend) have been used to interpret the Gathas, but by the 3rd century the Avestan language was vitually extinct, and a dependancy of the medieval texts is often discouraged as the commentaries are frequently conjectural. While some scholars argue that an interpretation using younger texts is inadvisable (Geldner, Humbach), others argue that such a view is excessively skeptical (Spiegel, Darmesteter). The risks of mis-interpretation are real, but lacking alternates, such dependancies are perforce necessary.
There are three monumental translations of the Gathas worth noting: The earlier James Darmesteter version ('Zend-Avesta III, SBE 31, 1887) which is based on a translation "from below", that is, based on the later middle Persian commentaries and translations. The other two are Helmut Humbach's The Gathas of Zarathushtra (Heidelberg, 1959, repr. 1991), and Stanley Isler's The Gathas of Zarathustra (Acta Iranica IV, Leiden, 1975), both of which exploit the "Vedic" approach.
Other verses, from which some aspects of Zoroaster's life have been inferred, are semi-(auto)biographical, but all revolve around Zarathustra's mission to promote his view of the Truth. For instance, some of the passages describe Zarathustra's first attempts to promote the teachings of Ahura Mazda, and the subsequential rejection by his kinsmen. This and other rejection led him to have doubts about his message, and in the Gathas he asked for assurance from Ahura Mazda, and requests repudiation of his opponents.
The various hymns appear to have been composed at different periods in his life, and read chronologically, a certain earnestness and conviction in his message are apparent. While in earlier verses, Zarathustra occasionally expresses his doubts on his own suitability of the mission, he never wavers in his conviction that the message is correct. A tone of contentment and belief in his vindication is apparent only in the last few hymns, and to the last, where he officiates at the wedding of his youngest daughter, he remains the persevering predicant.
Aspects of Zoroastrian philosophy are distributed over the entire collection of Gathas. There is no systematic arrangement of the doctrine of Zarathustra in the texts.