No astral soul, even that of a pure, good, and virtuous man, is immortal in the strictest sense; "from elements it was formed--to elements it must return." Only, while the soul of the wicked vanishes, and is absorbed without redemption, that of every other person, even moderately pure, simply changes its ethereal particles for still more ethereal ones; and, while there remains in it a spark of the Divine, the individual man, or rather, his personal ego, cannot die. "After death," says Proclus, "the soul (the spirit) continueth to linger in the aerial body (astral form), till it is entirely purified from all angry and voluptuous passions . . . then doth it put off by a second dying the aerial body as it did the earthly one. Whereupon, the ancients say that there is a celestial body always joined with the soul, and which is immortal, luminous, and star-like."
Isis Unveiled Chapter XII