The teachings of the great teacher were, after his death, taken over by priests who changed and added to the original teachings. The Avesta teachings were, at first, only taught by word of mouth, and the explanation (Zend or Zanti) also, by the Zend people, meaning those who studied and lived according to the teaching, so they could explain to the others; only much later the teachings were written down.

Before they were written down with alphabetic letters (in "Gathic" or "Avestan" words) though, a system of pictographic symbols was used to aid the remembrance of the texts, including their spiritual, deeper meaning: the so-called "Zend" or "Zanti." The positive symbols were white, the negative symbols were stamped into the then used clay tablets with black ink. Each symbol could have several meaning in spoken words, as you may still find in oriental languages.

For instance could mean Love, Good Words or/and to speak to-, just like could stand for Wisdom and/or Good Thoughts, or could stand for Power as well as for Good Deeds. This system was and is used by all the initiated pupils of the great teacher, who received the Pure, Original teaching of the Zend Avesta, that means : the teachings of the Avesta, PLUS the all-important Zend: the way of interpreting them! In later times, conquerors of the Aireanem Vaejo, the home of the great teacher (The Persian Empire, later Iran), and representatives of all the later priest-formed organized faiths have done their best to destroy any surviving clay tablets of the Great Teaching. But they survived, carefully hidden by the followers of the Original, Pure, Good Teaching. Comparison of the later versions of the Zend Avesta Texts with the clay tablets easily shows additions and changes to those who understand.

Some of the symbols as used on the hidden Avestan clay tablets

Much later, a revival of the Zend Avesta teachings was supported by the worldly rulers of the time, and by a convention of priests-scientists who were invited to come from Saïs in Egypt, with Persian astrologers and scientists, one of the most ancient calendars was constituted. But what is more interesting : every month was given 30 days (the 12 months supplemented with 5 Gatha Days to get a year of 365 days) of which every day represented a part of the Zend Avesta. This system of names is still in use!
To know just HOW to live according to the three G's, for each day one could study a theme from the Ancient Teaching in the Zend Avesta, which would eventually give the wisdom to ,make all the right decisions. Every week of the month stood for a phase in the life of a human being. 

1. The First Week (days 1-7) celebrates the Creator (Ahura Mazda) and his Amesha Spentas, or Archangels

2. The Second Week (8-14) celebrates LIGHT and NATURE

3. The Third "Week" (15-22) celebrates Moral Qualities

4. The Fourth "Week" (23-30) celebrates Religious Ideas, or the way back to "Heaven"

Click below, to go to the 30 DAYS or SIROZA, and learn about the the different themes belonging the 30 days of the Avestan month.

Other divisions of timewhich were made, with Gathic (Avcestan) names :

Each Year was divided into

 And because 12 x 30 makes 360, the Year was replenished by adding

Every Day was divided into

And to be able to distinguish the seasons, the year was also divided by

The last ten days of the religious year