Alain Danielou – While the Gods Play 

Monotheism reduces the celestial hierarchies to a single figure with whom prophets and pontiffs claim to communicate; this figure places upon them the responsibility of enforcing so-called moral and social laws of human invention, just as if man were the centre of the universe and the reason for its existence.

Monotheistic religions are, moreover, mutually exclusive, each one receiving contradictory instructions from its god. 

A type of dualism comes into being when the creative principle is personalized and separated from what is created. This leads to contempt for the divine work, which man can then exploit as he pleases, referring to the instructions revealed to him by a fictitious personality, and which in fact are merely the projection of his ambitions, his wish for power, and the subjection of nature to his depredations.

"A monistic god paves the way for subsequent productivity and introduces totalitarianism" (Michel Maffesoli, L'Ombre de Dionysos, p. 53).

It is this reduction of the subtle active forces to a single divine being which has allowed the monotheistic religions to become instruments of obscuratism and oppression, culminating in the ridiculous behaviour of the religious sects characteristic of modern times, from the Inquisition to Khomeinism.  The fiction that is monotheism will allow any tyranny.

The shaman and the medium are quite right to believe that they can receive information from the intermediary powers, whereas the high priest who claims to embody the will of a universal principle outside creation can only be a madman, a liar, or a charlatan.

A denial of a single god by no means includes a denial of the supernatural. Monotheism itself is in fact close to atheism; it prepares the way for materialism by replacing with an abstraction the reality of the celestial powers who are the gods.