The greatness and importance of Om Namo Narayanaya is mentioned in the Taraka Upanishad.
Om Namo Narayanaya is the Taraka. It should be worshipped as Chidatma.
Om is a single syllable and of the nature of Atma.
Om Namo Narayanaya is the Taraka. It should be worshipped as Chidatma.
Namah is of two syllables and is the nature of prakriti (matter).
He who knows this becomes immortal.
Through Om , is Brahma produced; through Na is Vishnu produced; through Ma is Rudra produced; through Na is Ishwara produced; through Ra is the Anda-Virat (or Virat of the universe) produced; through Ya is Purusha produced; through Na is Bhagavan produced; and through Ya is Paramatma produced.
This Ashtakshara (eight syllables) of Narayana is the supreme and the highest Purusha.