Elements are a special kind of substance, both ethereal and corporeal, and they also possess excellent compatibility. This characteristic allows them to blend with nearly everything in the world and transform into new, controllable energies.
That was how magic power originated; it is an imitation of the Almighty Divine Power, a product of spirit and element merging and sublimating. However, the magic power strived for elevation—it grew stronger with the mental will of the spellcasters; but the force in Zeus's hands was not like this.
It was a degradation of Divine Power, a dilution and blunting. What determined its potency was the extent of dilution, and the proportion of Divine Power in it could never exceed one-twelfth.