Dear Ramesh Mishra ji
The mantra you state is the most famous Narayana astakshari. Astakshari means eight akshara.
om na-mo naa-raa-ya-Naa-ya
1 2 3 4 5 6 7 8 = 8 akshara [Akshara = energy inflow, final result] = 8th house
1 2 3 = 3 words [Words = energy outflow, start of count] = 3rd house
Now count from 3rd house to 8th house, we get 6 houses
Now count as many houses from the 8th house. In this example we got 6 houses, so when we count six houses from 8th house, we get Lagna as the answer.
Final result = Naarayana is in LAGNA.
So the mantra devata Narayana sits in lagna and the recitation of this mantra gives good health, protection from all evils, long life and clear intellect. It is the greatest mantra for lagna suddhi and is one of the three mantras of the Narayana Kavacha. The greatest strength of this mantra is that it removes all kinds of nija dosha indicated by the 8th house or 8th lord and makes the lagna very strong.
Now study the dhyana or the meditation of the mantra devata. It starts as 'dhyaye sadaa savitrimandala madhyavarti Naaraayana..' and the reference is to the Sun which is the significator of Lagna and that Naraayana is in the centre of the solar orb.
The best mantras of the devatas always fall in the correct houses indicated for them. Then such mantra are called Prasiddha mantra and such mantra can only be originally given by the seers as they alone had such great sight and knowledge.
1 2 3 4 5 = 5 akshara = 5th house
1 2 = 2 words = 2nd house
Count from 2nd house to 5th house, we get 4 houses
Now count 4 houses from 5th house and we get 8th house. This is the house of Rudra and the panchakshari mantra has the power to give great knowledge as it cleanses the fifth house and finally this causes protection from all evils of 8th house where Shiva sits to protect you and grant longevity.
In this manner study the following
1. Surya astakshari
om ghri-ni suu-ry-aa-di-tya
1 2 3 4 5 6 7 8 = 8 akshara
1 2 3 = 3 words
Mantra devata = 1st house (Lagna)
What happens when this is pronounced differently by breaking surya and aaditya
om ghri-ni suu-rya aa-di-tya
1 2 3 4 5 6 7 8= 8 akshara
1 2 3 4 = 4 words
Mantra devata = 12th house in marana karaka sthana
See the change how the position of the mantra devata changes from Lagna to the 12th house which is the marana karaka sthana for Sun.
Thus while reciting the mantra if the words are not spelt jointly as indicated it can do a lot of harm.
1. om namo bhagavate vaasudevaaya
2. om namah shivaaya
3. om kshraum namo bhagavate narasimhaaya
4. om bhur namo bhagavate vyankateshaaya
5. brm brhaspataye namah
6. om namo bhagavate rudraaya
7. om namo bhagavate mahaamatsyaaya
8. gajamukha siddhirastu
9. hare raama krsNa
10. om hrim shrim krim paramesvari kaalike svaahaa
11. om namo bhagavate akuparaaya
12. vyam vedavyaasaaya namah
...just a start. I will give more exercise when we meet next sunday and explain from charts how to choose.
With best wishes and warm regards,
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Sri Jagannath Center®
15B Gangaram Hospital Road
New Delhi 110060, India
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