The Way of the Bodhisattva by Shantideva  is a Mahayana Buddhist text written c. 700 AD in Sanskrit verse. 

“The aim to work for the benefit of beings,

A benefit that others wish not even for themselves.

This noble, jewel like state of mind

Arises truly wondrous, never seen before.”

 

“I therefore have no thought that this might be of benefit of others,

I wrote it only to habituate my mind.”