Nāḍī-saṁhāra-bhūta-jaya-bhūta-kaivalya-bhūta-pṛthaktvāni (sūtra III.5)
Nāḍī – bodily channels through which prāṇa flows; saṁhāra – withdraw; bhūta – gross elements; jaya – subjugation; kaivalya – isolation; pṛthaktvāni (pṛthaktva) – detachment.
Further guidance is given to control the mind in this sūtra. Nāḍīsaṁhāra means withdrawing the flow of prāṇa from other channels and making it to flow through suṣumna. If this is practiced, it leads to bhūtajaya, subjugation of gross elements and subsequent isolation of mind (bhūta-kaivalya) from gross elements. This detachment (bhūta-pṛthaktva) is to be contemplated through thought process.
By practicing breath control, one is able to activate his spinal cord, also known as suṣumna. Apart from practicing certain yogic exercises and breath control, while activating suṣumna, one’s visualisation is important. One has to seriously contemplate that he is subjugating all other nerve channels by activating suṣumna. When activation of suṣumna is properly visualized or one is able to mentally affirm that his suṣumna is activated, he is able to isolate his consciousness from the influence of gross elements that are responsible for sensory influence. When this happens, an aspirant is able to detach his consciousness from his gross body, leading to non-realisation of bodily miseries. Misery plays havoc both on physical body and mind. Bodily miseries are realised only when one is aware of his body. If he is able to detach bodily sensations from this though process, the sufferings of the body are not realised. When bodily sufferings are not realised by the mind, it undergoes the first purification process. When suṣumna is properly activated, rest of the process of realisation automatically unfolds for a true aspirant.