the god challenged the right of the Blessed One to be sitting there, beneath the Bo Tree, on the Immovable Spot; whereupon the Future Buddha only touched the earth with the tips of the fingers of his right hand and the earth thundered
Zimmer establishes the Bo Tree as the site of the Buddha’s cosmic confrontation with Māra, where the earth herself bears witness to the Bodhisattva’s right to occupy the axis of enlightenment.
, Philosophies of India, 1951thesis