Soham is a reversal form of Hamsa. It is the combination of words Sa and Aham whereas Hamsa is the combination of Aham and Sa. It means He I am. I am the Supreme God. It is also an Ajapa Gayatri Mantra.
Isopanishad verse 16 says,
pūṣannekarṣe yama sūrya prājāpatya vyūha raśmīn samūha tejaḥ । yatte rūpaṃ kalyāṇatamaṃ tatte paśyāmi yo'sāvasau puruṣaḥ so'hamasmi ॥ 16॥
“My Lord! Primeval Entity! Maintainer of the Worlds! Regulator of the Universe! the goal of the pure devotees! the well-wisher of all beings! please remove the brightness Your transcendental rays so that I can see Your form of bliss. You are the eternal Supreme Entity of divinity, like the sun, like I am.”
Hamsa and Soham
Though the meaning of the two terms Hamsa and Soham are the same, their application in Japa is slightly different. Hamsa Mantra Japa starts with exhalation with concurrent meditation upon the sound ‘Ham’ and ends with the completion of inhalation with the meditation upon the sound ‘Sa’; whereas Soham Mantra Japa starts with inhalation with ‘So’ and ends with the completion of exhalation with ‘Ham’.
The crude form of Mantra Japa as chanted by everyone should be fine-tuned to become Ajapa Gayatri. This Upasana is known as Hamsa Vidya. By Hamsa Vidya, one can control his Prana and Chitta. It results in Samadhi. Hence Samadhi is attained by Hamsa Vidya.
One of the earliest Upanishads, Brihadaranya Upanishad verse 1.4.1 says,
ātmaivedamagra āsītpuruṣavidhaḥ । so'nuvīkṣya nānyadātmano'paśyat so'hamasmītyagre vyāharat tato'hannāmābhavat ।
“In the beginning, Atman was there in the form of Purusa. Knowing that there was no second one except himself, he said I am He. (Soham asmi).”
Sohamasmi was the first word uttered by the primeval entity. It was the first word of first sentient Being.
Mahavakya Upanishad says,
asāvādityo brahmetyajapayopahitaṃ haṃsaḥ so'ham
“The knowledge that the Sun is Brahman is attained by the Hamsa Mantra: Soham”.
Yoga Sikha Upanishad
Yoga Sikha Upanishad (1.131-2) says,
haṃsahaṃseti mantro'yaṃ sarvairjīvaśca japyate । guruvākyātsuṣumnāyāṃ viparīto bhavejjapaḥ ॥ 131॥ so'haṃso'hamiti prokto mantrayogaḥ sa ucyate । pratītirmantrayogācca jāyate paścime pathi ॥ 132॥
“For all beings, Prana goes out with the sound ‘Ha’ and comes in with the sound ‘Sa’. This generates the Mantra ‘Hamsa, Hamsa’. Under the guidance of a Guru and during the course of Sushumna Yoga, the Mantra Japa gets reversed and it becomes ‘Soham, Soham’. This is called Mantra Yoga.”
Steps in Soham Mantra Japa
- Sit in a comfortable posture that is convenient for you.
- Close your eyes and fix your internal eyes at the tip or base of your nose.
- Watch your breath.
- Conceive the sound ‘So’ with inhalation and ‘ham’ with exhalation.
- During this Japa, meditate that ‘He I am’: I am the Supreme Entity.
- Continue this Japa and Meditation for at least 10 to 15 minutes.
- Repeat the process daily at the same time and for the same duration.
- Increase the duration in a phased manner.
- Slowly ingrain the process passively during all the activities of the daily routine.
- When you are accustomed to doing this constantly all the time, it becomes Ajapa Gayatri.
Gayatri means the chanted mantra that saves. Gayatri is the supreme mantra that saves the one who chants. Ajapa Gayatri is the supreme Mantra that does not fall under the chanted category and yet saves the one who performs.
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