This rudimentary eschatology, however, gave way to quite a different conception, one that was closely related to the Chaldean astrology, and which spread over the Occident towards the end of the republic. According to this doctrine the soul returned to heaven after death, to live there among the divine stars. While it remained on earth it was subject to all the bitter necessities of a destiny determined by the revolutions of the stars; but when it ascended into the upper regions, it escaped that fate and even the limits of time; {126} it shared equally in the immortality of the sidereal gods that surrounded it.[60] In the opinion of some, the soul was attracted by the rays of the sun, and after passing through the moon, where it was purified, it lost itself in the shining star of day.[61] Another more purely astrological theory, that was undoubtedly a development of the former, taught that the soul descended to earth from the heights of heaven by passing through the spheres of the seven planets. During its passage it acquired the dispositions and qualities proper to each planet. After death it returned to its original abode by the same route. To get from one sphere to another, it had to pass a door guarded by a commandant ([Greek: archon]).[62] Only the souls of initiates knew the password that made those incorruptible guardians yield, and under the conduct of a psychopompus[63] they ascended safely from zone to zone. As the soul rose it divested itself of the passions and qualities it had acquired on its descent to the earth as though they were garments, and, free from sensuality, it penetrated into the eighth heaven to enjoy everlasting happiness as a subtle essence. Perhaps this doctrine, undoubtedly of Babylonian origin, was not generally accepted by the Syrian religions, as it was by the mysteries of Mithra, but these religions, impregnated with astrology, certainly propagated the belief that the souls of those worshipers that had led pious lives were elevated to the heights of heaven, where an apotheosis made them the equals of the luminous gods.[64] Under the empire this doctrine slowly supplanted all others; the Elysian fields, which the votaries of Isis and Serapis still located in {127} the depths of the earth, were transferred into the ether bathing the fixed stars,[65] and the underworld was thereafter reserved for the wicked who had not been allowed to pass through the celestial gates.