However, the astral body (or "Soul body") must be evolved by means of the work of transmutation and will eventually be evolved by humanity as a whole. According to Heindel, the term "astral body" was employed by the mediaeval Alchemists because of the ability it conferred to traverse the "starry" regions. The "Astral body" is regarded as the "Philosopher's Stone" or "Living Stone" of the alchemist, the "Wedding Garment" of the Gospel of Matthew and the "Soul body" that Paul mentions in the First Epistle to the Corinthians