20:6.4

When a bestowal Son has mastered the experience of living the mortal life, when he has achieved perfection of attunement with his indwelling Adjuster, thereupon he begins that part of his planetary mission designed to illuminate the minds and to inspire the souls of his brethren in the flesh. As teachers, these Sons are exclusively devoted to the spiritual enlightenment of the mortal races on the worlds of their sojourn.