You may control a mad elephant; You may shut the mouth of the bear and the tiger; Ride the lion and play with the cobra; By alchemy you may earn your livelihood; You may wander through the universe incognito; Make vassals of the gods; be ever youthful; You may walk on water and live in fire; But control of the mind is better and more difficult.
When your sense of self is no longer tied to thought, is no longer conceptual, there is a depth of feeling, of sensing, of compassion, of loving, that was not there when you were trapped in mental concepts. You are that depth.
I reached in experience the nirvana which is unborn, unrivalled, secure from attachment, undecaying and unstained. This condition is indeed reached by me - deep, difficult to see, difficult to understand, tranquil, excellent, beyond the reach of mere logic, subtle, and to be realised only by the wise.
