Atman alone manifests and shines without form, in pristine clarity

Verse 51

तस्यापि निरोधे सर्वनिरोधान्निर्बीजः समाधिः ॥५१॥

tasyāpi nirodhe sarva-nirodhān-nirbījaḥ samādhiḥ ॥51॥

By the restraint of even this (impression, which obstructs all other impressions), everything is restraint, comes the Nirbija (seedless) Samadhi.

The sadhaka must learn to restrain even this new impression of truth-bearing light. 

When both old and new impressions are dissolved, a state of seedless enlightenment arises, in which all illusions and delusions has come to an end

This is nirbija samadhi: the state of absolute identity with the seer.

Just as a flame is extinguished when the wood is burnt out, or as rivers lose their existence on joining the sea, all impressions of the unconscious, subconscious, conscious mind cease to exist. 

All these rivers of consciousness merge in the ocean of the seer.

Nirbija samadhi is the conquest of the chitta wherein the root mind is one with the seer.

As all thoughts are brought to an end by practice and detachment, the Jiva is freed from the shackles of earthly

vehicles: the body, senses, mind, intelligence.

When chitta is dependent upon an object, idea or symbol, the state is called sabija samadhi.

In nirbija samadhi, chitta dissolves and no residue of impressions remains. All residual impressions, the thinking faculty and the feelings of 'I' are extinguished without trace and become universal. 

Then the Atman alone manifests and shines without form, in pristine clarity.

PATANJALI YOGA SUTRAS