The whole universe is Consciousness vibrating at different frequencies. All the varying techniques of yoga(union) and meditation are based on the underlying principles of resonance and sympathetic vibration.
Through atunement with a particular state of consciousness we become it. Atunement means aligning our variables so that they correspond with the state we are trying to attain.
What are the variables which we have to work with? They are such things as posture, colour, our actions and the words that we intone.
Sacred alphabets such as Sanskrit are said to embody the complete spectrum of universal forces. By utilizing the science of mantra we may harness this awesome power- this power of vibration which is the basis for the whole of Creation.
It has often gone unrecognized however that the power of mantra yoga affects us all whether we are aware of it or not.
When ever we speak silently to ourselves or out loud we are influenced by the quality of the vibrations which we are giving out.
Imagine that you heard two people arguing in a foreign language which you could not understand. You would be able to get a feel for what was been said by the actual quality of the sound being produced.
It is not then necessary to know the ins and outs of the exact nature of sacred alphabets nor to be empowered by a Guru in order to benefit from the science of mantra.
By being mindful of the quality of our speech we will be making an important contribution to our well being.
If you ever catch yourself talking harshly, with unkindness or moaning in a victim like way know that you are actually intoning a negative although weak mantra.
With this awareness, relax and uplift the quality of your speech. Imagine the ideal: rich, confident and compassionate tones and aim for that. An understanding of the virtues is useful in imagining the ideal. Be sure then to study "Inner Medicine" for a deeper appreciation of the virtues.
One of the reasons for the differences in national character is because of the particular language habitually used. Even same language regional differences in character and accent have a mutual effect on each other.
It can be useful to see your own character and speech in the context of regional influences so as not to be restrained by them.
Whilst it is true that general speech is important, there can be no doubt that more advanced mantra practices are far more powerful. Why is this?
Well as stated earlier atunement is connected with optimizing variables. By sitting in the correct posture, by wearing natural loose fitting clothing of a particular colour, by gazing at a sacred image at the same time as reciting the mantra with conscious intent and understanding its meaning then we are harnessing far more of the variables available to us: thus having a correspondingly greater effect.
Where as the letters vocalized in everyday speech have a more or less random(or certainly unintentional) effect a true Mantra is constructed specifically with a goal in mind. This means that the intention energy is much more focused. It also means that the letters are chosen for their innate and non-arbitrary vibrational effect.
It is also said that by using a mantra given to us by a genuine realized soul the blessings are greater still.
Firstly such a realized soul, being aware of our imbalances etc, can prescribe us with a mantra/medicine ideally suited to our temperament. Secondly it is said that such a mantra is empowered by the blessings of the teacher. These blessings are partly due to morphic resonance and partly intelligent spiritual intervention at subtle levels.
If you really want to understand mantra yoga then you must study the sacred alphabets, the different types of letter and so on. Study many different schools of thought on the subject and try to get to the deeper meanings below the rubbish which inevitably creeps into these subjects.
I would say though that for most students this is unnecessary: Good natured intent and simple effort being more beneficial than what can become a distracting dry intellectual exercise.
Practicing diligently to uplift our every day speech is a noble yoga indeed.