Śrīmad-Bhāgavatam · Text 2.1.17
Who is speaking and story frame
अभ्यसेन्मनसा शुद्धं त्रिवृद्ब्रह्माक्षरं परम् ।
मनो यच्छेज्जितश्वासो ब्रह्मबीजमविस्मरन् ॥ १७ ॥
abhyasen manasā śuddhaṁ
trivṛd-brahmākṣaraṁ param
mano yacchej jita-śvāso
brahma-bījam avismaran
After sitting in the above manner, make the mind remember the three transcendental letters [a-u-m], and by regulating the breathing process, control the mind so as not to forget the transcendental seed.
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