Śrīmad-Bhāgavatam · Text 4.31.3
Who is speaking and story frame
तान्निर्जितप्राणमनोवचोदृशो
जितासनान् शान्तसमानविग्रहान् ।
परेऽमले ब्रह्मणि योजितात्मन:
सुरासुरेड्यो ददृशे स्म नारद: ॥ ३ ॥
tān nirjita-prāṇa-mano-vaco-dṛśo
jitāsanān śānta-samāna-vigrahān
pare ’male brahmaṇi yojitātmanaḥ
surāsureḍyo dadṛśe sma nāradaḥ
After practicing the yogāsana for mystic yoga, the Pracetās managed to control their life air, mind, words and external vision. Thus by the prāṇāyāma process they were completely relieved of material attachment. By remaining perpendicular, they could concentrate their minds on the uppermost Brahman. While they were practicing this prāṇāyāma, the great sage Nārada, who is worshiped both by demons and by demigods, came to see them.
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