SB 9.15.31
yato yato ’sau praharat-parasvadho
mano-’nilaujah para-cakra-sudanah
tatas tatas chinna-bhujoru-kandhara
nipetur urvyam hata-suta-vahanah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Lord Parasurama, being expert in killing the military strength of the enemy, worked with the speed of the mind and the wind, slicing his enemies with his chopper [parasu]. Wherever he went, the enemies fell, their legs, arms and shoulders being severed, their chariot drivers killed, and their carriers, the elephants and horses, all annihilated.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
In the beginning, when the army of the enemy was full of fighting soldiers, elephants and horses, Lord Parasurama proceeded into their midst at the speed of mind to kill them. When somewhat tired, he slowed down to the speed of wind and continued to kill the enemies vigorously. The speed of mind is greater than the speed of the wind.