INNER STILLNESS 

When the brain is completely empty and silent, it is in contact with the Universal energy. It happens necessarily because the inner stillness is the same stillness, order and void that is the Universe.

This is known as Unitary Perception, Universal Perception, Dhjana, Zen, Yoga, etc.

A busy, occupied brain (pursuing goals, security, control, choices, pleasures, etc) can never find it, so all those have to be suspended. The brain cannot be tied in any way to created things or worldly desires. 

UP is not an experience, "consciousness" (as we know it: subject - object) or sensation that thought can find, it is the negation of seeking. It's beyond time and memory.

The purest detachment completely lets go of all created things and the self//the me/my will. It rests on nothing, wants nothing and knows nothing.

What is the essence of all things, from where everything, the tree, the bird and the man, comes from and where it returns? 

Everything, the bird, the tree and the man are only transitory changing forms. There is nothing in this world that does not change, transform. There is nothing in this world to which one can attach oneself and find security.

Predicting and pursuing goals (where concentration and the horizontal conflict of subject - object is necessary) can be balanced with resting in complete peace.