In the fragments of the Avesta which have come down to us we find invocations addressed to the "time without beginning," "the time that rules the long periods."[145] But the fact that Yima's reign is fixed at 1000 years shows that the priests of Iran reckoned by long periods, and other expressions in the Avesta (p. 33) prove that triple multiplications were in use,[146] which agrees with the periods given by Theopompus. If, therefore, the Greeks of the fifth and fourth century B.C. relate that Zarathrustra lived about 6000 years before their time, a system must by that time have been current among the priests of Iran in which two cycles of 3000 years were supposed to have elapsed since the time of the prophet, and the third cycle had commenced. A book of the Parsees, the Mainyo-i-Khard, which appears to have been written towards the close of the empire of the Sassanids,[147] tells us that Angromainyu made a compact with Auramazda for 9000 winters, and when these winters were past, Angromainyu would be destroyed, and the creation and all creatures would be as Auramazda had made them.[148] The Bundehesh also speaks of a similar compact, but divides the years in a different manner. All time consists of 12,000 years. In the first 3000 Auramazda reigned alone with the creatures which he had created in an invisible manner; for the first 3000 of the next 9000 everything went according to the will of Auramazda; for the second 3000 the will of Auramazda was crossed by that of Angromainyu, but for the last 3000 Angromainyu will be powerless. The Bundehesh goes into yet further detail in these matters: in the first 3000 years the heavenly creation was secure from attack; in the next 3000 Gayo maretan and the ox, _i.e._ the first man and the first bull, came into existence. After these 6000 years the enemy arose and slew the first man and the first bull. The reign of Yima is placed by the Bundehesh in the first millennium of the new period, but this reign extends only to 716 years, the first 284 years of the thousand being filled with creatures prior to Yima. The second millennium of the period is occupied with the reign of Thraetaona, Manuschithra, Kava Kavata, Uça, Huçrava, and Aurvataçpa, and the early part of the reign of Kava Vistaçpa, whose thirtieth year coincides with the end of the second millennium.[149] At the beginning of the third millennium, _i.e._ a thousand years after the death of Yima, Zarathrustra appears; and the period of more successful opposition to the evil spirits begins. According to the more ancient conception, which may still be plainly traced in the Avesta, the world began with the happy age of Yima; it is owing to later views formed within priestly circles that earlier creatures such as the first man and first bull are placed before this period; but it will be shown below that these views existed when the Avesta was written down. A later book of the Parsees, the Sad-der-Bundehesh, puts the period of the conflict between the good and evil deity at 6000 years, and places Zarathrustra exactly in the middle of it; he was created 3000 years after the period of Gayo maretan, and 3000 years before his own resurrection.[150] Hence it is clear that the formation of these cycles rose among the priests of Iran from the necessity of limiting the period of the old and new law, and of conflict between the good and evil spirits, and the desire to fix the date of the more successful repulse of evil which came in with Zarathrustra. The abbreviation of the period of Yima shows us that the cycles in the Bundehesh do not throughout agree with those of the Avesta. But it is sufficient to establish the fact that periods of 3000 years were in use, and that Zarathrustra appeared at the beginning of a new millennium, in order to understand that the Persians could speak to the Greeks of millenniums in this sense, and of one or two cycles which had elapsed since Zarathrustra's time.