This theory of mass believe empowering “thought forms” breaks down when you consider that people in ancient times were able to constrain spirits with YHVH or Jesus name before there was a billion Christians.
I disagree respectively, this would mean hypothetically that If I had a Superior believe in myself above all other people as the best mage/wizard in the world then everyone else would be the weakest as a result.
If believe was the defining factor of power.
To me power is not relative, it’s definitive. There are those that have it and those who don’t and never will.
(in regard to spiritual, mental and physical power)
There are various powers in the Universe and they are not equal, they are Hierarchical.
Symbols and spirits can embody or represent these various powers in respect to their hierarchical placement, and humans can use them to tap into those powers through training and initiation.
I do agree that the path of devotion plays a role, but at that point its not at the behest of the devotee but the spirit or god in question that the power or “effect” comes about.
In my observation and experience, the universe is not subjective or chaotic and random, it’s in fact very structured and hierarchical, because of this fractal nature “as above so below” some powers are closer to the earth, anciently known as “Sublunary” spirits and others are more Transcendental.
So it could be the case with Jehovah that it symbolizes or partakes in the Transcendental powers and therefore exerts more authority over the Sublunary spirits. I personally don’t think it IS the top of the spiritual hierarchy of power, but that it borrows from it.
This is the spiritual element in magic in regard to the individual and his/her relationship to the cosmos, then next comes the Mental and Physical.
Yes it very well can, but the physical matter is not empty and dead before magician picked it up and projected his power through it.
On the contrary, matter is imbued with both Physical, Mental and Spiritual energies/attributes.
This is proven by anyone who trained in the Hermeticism of Franz Bardon who spoke of the Electric and Magnetic “fluids” that all matter can possess, or those who have studied and practiced Alchemy.
(like myself)
Matter is not dead it’s vibrant with all kinds of powers, “matter is alive!” as the animists would say.
That it’s Spiritual attributes, we are already aware of matters Physical attributes, next would be its Mental.
This comes in the form of it’s symbolism. like Gold color symbolizing the Sun and possessing the spiritual electric fire just to name a few. These symbols play are large role in communication to our consciousness the occult powers laden within.
(these symbols likewise are not subjective, but are Archetype and Universal.)
So in conclusion, the cosmos is structured, matter has purpose/attribute and when a focused and trained being utilizes these powers holistically Mind, Body, Spirit the miraculous takes place within their respective hierarchy, the human mind when perfected residing at the top.
Thank you. 
