Mantra yoga is an exact science. Manana trayate iti mantrah By whose manana (constant thinking or recollection) one is protected or released from the cycle of birth and death is mantra. A mantra is so called because it is achieved by the mental process. The root man in the word mantra means to think, and tra comes from trai meaning to protect or to free (from the bondage of samsara, the phenomenal world).
Mantra is divine power manifesting in a sound body. It is a mass of radiant energy, tejas, which is awakened through the sadhana shakti (power of spiritual practices) of the aspirant. All mantras have equal potency or power. Some people think that Om or Soham is superior to Om namo Narayanaya, or vice versa. This is wrong. The state gained by doing japa of Om or Soham can be attained by doing japa of Sri Ram, Radheshyam or any other mantra.
Every mantra has six parts. It has a rishi who had self-realization for the first time through the mantra and who gave the mantra to others. Sage Vishwamitra, for example, is the rishi for the Gayatri mantra. Every mantra has a metre. It has a presiding deity (ishta devata). It has a bija (seed), which is its essence. It has its own shakti, energy. Lastly, it has a kilaka (pillar or pin) which plugs the chaitanya (consciousness) hidden in the mantra. When the plug is removed by constant and prolonged repetition, the chaitanya is revealed.
Sound is vibration. It gives rise to form. Combinations of sounds create complicated shapes. Scientific experiments have shown that rhythmical vibrations give rise to regular geometrical forms. Repetition of mantra gradually builds up the form of its deity.
The repetition of Om namah Shivaya produces the form of Shiva. The repetition of Om namo Narayanaya produces the form of Vishnu. In mantra practice, the vibrations produced by the note are all-important. Therefore, emphasis is laid on the pitch (swara) as well as form (varna) of the mantra. Varna literally means colour. In the invisible world all sounds are accompanied by colours. Different notes in different pitches give rise to different shapes. In the science of mantra, different mantras are used to invoke different gods.
What happens when the mantra is recited? The repeated recitation of the mantra produces in the mind the form of the deity connected with the mantra, and this form becomes the centre of your consciousness when you directly realize it. It is therefore said that the mantra of the deva is the deva himself. This may explain the much misunderstood dictum of mimamsa philosophers that the gods do not exist apart from the mantra (mantratmako devah).
Initiation into the divine name or mantra diksha is one of the most significant rituals in spiritual life. To receive the guru mantra from a realized saint is the rare fortune of an aspirant. A tremendous transformation begins to take place in the innermost core of the initiated. The significance of mantra diksha is indicated in a story about Vishnu and Narada.
After the divine sage Narada had departed from Lord Narayanas presence in Vaikuntha, the Lord directs Lakshmi to sprinkle water on and clean the spot occupied by Narada during his short stay. When Lakshmi enquires in astonishment the reason for this procedure, the Lord explains that this is because Narada has not yet been initiated, meaning thereby that the mysterious inner purification that is bestowed by mantra diksha had not yet come to him.
The initiated himself is unaware of the glory of initiation because of the veil of ignorance (moola-ajnana) that still covers him. Nevertheless, the transformation starts with initiation, and like a seed that is sown in the earth, ultimately culminates in the fruit of realization.
To reach fruition, as the seed has to pass through a process of developing into a seedling, a plant, and then a full-grown tree, the aspirant must make earnest and continuous effort. This part is the aspirants sole responsibility in which he will doubtless receive the help, guidance and grace of the guru in the measure of his faith and devotion.
The glory of mantra cannot be established through reasoning and intellect. It can only be experienced or realized through devotion, faith and repetition. When you do japa, repetition of mantra, have the feeling or attitude that divinity is seated in your heart, that sattwa or purity is flowing from the divine to your mind. Do not do japa in a hurried manner, do it slowly with bhava and one-pointedness of mind. It is always better to adopt a medium speed in japa. Of course, there is one advantage in doing japa with electric speed. If the mind is dull or wandering wildly, high speed japa for fifteen or thirty minutes will stabilize it.
In the Bhagavad Gita it has been said (10:25):
Yajnanam japa yajnosmi.
Among yajnas, I am japa yajna.
There is no yoga greater than japa yoga. Japa checks the force of the thought currents moving towards objects. It forces the mind to move towards divinity. Constant and prolonged repetition cuts new grooves in the mind. During japa, divine qualities steadily flow into the mind just as oil flows from one vessel to another. Japa transforms the nature of the mind. It changes the mental substance from passion to purity, from rajas to sattwa. It calms and strengthens the mind, makes it introspective, eradicates negative thoughts, induces determination and austerity, and eventually leads to the direct darshan or realization of divinity.
The mind is purified by constant japa. When the mind thinks of the image of divinity during japa, the mental substance actually assumes the form of the image. The impression of the object is left in the mind. This is called samskara. When the act is repeated often, the samskaras gain strength and a tendency or habit is formed. One who entertains thoughts of divinity becomes transformed into divinity itself. The meditator and the meditated, the worshipper and the worshipped, the thinker and the thought, become one. This is samadhi. This is the fruit of japa.