“Q: But do not our minds receive their illuminations direct from the Higher Manas through the Lower? And is not the former the pure emanation of divine Ideation – the “Manasa-Putras”, which incarnated in men?
A: They are. Individual Manasa-Putras or the Kumaras are the direct radiations of the divine Ideation – “individual” in the sense of later differentiation, owing to numberless incarnations. In sum they are the collective aggregation of that Ideation, become on our plane, or from our point of view, Mahat, as the Dhyan-Chohans are in their aggregate the Word or “Logos” in the formation of the World.
Were the Personalities (Lower Manas or the physical minds) to be inspired and illumined solely by their higher alto Egos there would be little sin in this world.
But they are not; and getting entangled in the meshes of the Astral Light, they separate themselves more and more from their parent Egos. Read and study what Eliphas Levi says of the Astral Light, which he calls Satan and the Great Serpent.
The Astral Light has been taken too literally to mean some sort of a second blue sky. This imaginary space, however, on which are impressed the countless images of all that ever was, is, and will be, is but a too sad reality. It becomes in, and for, man – if at all psychic – and who is not? – a tempting Demon, his “evil angel”, and the inspirer of all our worst deeds.
It acts on the will of even the sleeping man, through visions impressed upon his slumbering brain (which visions must not be confused with the “dreams”), and these germs bear their fruits when he awakes.
Q: What is the part played by Will in dreams?
A: The will of the outer man, our volition, is of course dormant and inactive during dreams; but a certain bent can be given to the slumbering will during its inactivity, and certainly after-results developed by the mutual inter-action – produced almost mechanically – through union between two or more “principles” into one, so that they will act in perfect harmony, without any friction or a single false note, when awake.
But this is one of the dodges of “black magic”, and when used for good purposes belongs to the training of an Occultist.
One must be far advanced on the “path” to have a will which can act consciously during his physical sleep, or act on the will of another person during the sleep of the latter, e.g., to control his dreams, and thus control his actions when awake.”
H. P. Blavatsky
The Mark Of God: Understanding Your "I AM Presence" 