Nirbija Samadhi — Seedless Absorption, the Threshold of Liberation
Nirbija Samadhi is the highest state described in the first pada — absorption without any seed (bija) of future rebirth, without object, without content — pure consciousness aware of itself alone.
Sutra 1.51 describes Nirbija (seedless) Samadhi: even the samskaras deposited by the truth-bearing wisdom of Ritambhara Prajna are themselves eventually stilled, and consciousness rests in complete objectless awareness. No thought, no object, no subtle sensation — pure consciousness without any support. This state is the threshold of Kaivalya (liberation): the distinction between the observer and the observed has collapsed, and only the Seer remains, abiding in its own nature. The 'seed' metaphor is precise: ordinary samadhi states still carry the seeds of future mental activity, like seeds that could germinate. In Nirbija Samadhi, those seeds are roasted — they retain their form but have lost the capacity to sprout into future suffering.
When even these impressions are stilled, the seedless samadhi is attained.
Swami Rama explains in The Philosopher's Stone that Nirbija Samadhi cannot be described or transmitted conceptually — it can only be pointed toward through the progressive stilling of mental activity that the preceding sutras prescribe in such precise detail.
Yoga Sutras of Patanjali