The World Tree, seemingly unchangeable, millennia of slumber had altered nothing; the appearance that the World Tree maintained before it slept was indistinguishable from after it awoke.
This is the cornerstone of all power in this world, the source of Mana, the root from where the divine gestates.
Aside from Elves, everyone's Magic requires chanting, either praising Mana or extolling the divine. The potency of magic indeed originates from the gods, or rather… for races other than Elves, the power of magic comes from the divine manipulation of the World Tree's energy.
Elves do not need it, Elves do not need to extol the divine... because the divine, to some extent, stems from Elves or has countless ties with Elves and the World Tree, rather than the other way around.