The mantras below, though they emerge from different cultural contexts, all trace their lineage back to that universal language, to the Word that begat the great mystery as St. John spoke of.

I have used these mantras for some years now in varying degrees of consistency and frequency and can personally attest to their efficacy and value. As with any meditative practice, it is a good idea to take a few deep conscious breaths before beginning and to clear the mind as best as one can, to focus properly on the task at hand:

helion melion tetragrammaton
om bhur bhuvas suvar maha
om ah hung
aum
sssss mmmmm aahhh ooooo (as in oops) oohhh (as in oat) aaayy (as in ace) eeeee (as in eat)
omnis jaum intimo
om namah shiva
aloah va daath
ta ya ta om be kan ze be kan ze ma ha be kan ze rad za sa mud ga te so ha
om gate gate paragate parasamgate bodhi soha
om mani padme hum
om shanti shanti shanti-hee and/or amen amen amen

It is important, as with a number of meditative disciplines, to keep in mind that the benefit accrued from such a practice is to be shared with everyone, including non-human creatures. So you may wish to include a short petition as an endnote to your practice something like: may any merit attained through this practice be dedicated to the enlightenment of all sentient beings

Taken from: J Ocean Dennie

Mantras such as AUM are primordial sounds that emerge from the Void and the endless expanse of that which lies unmanifested. The opening lines of the Gospel of St. John the Beloved resonate with this truth: "In the beginning was the Word, the Word was with God, and the Word was God."

The interesting thing is that the force of the mantra is cumulative which means that the more the mantra is articulated, the more powerful it becomes cosmically and in your personal sphere of life. Mantras are particularly helpful tools in the early stages of awakening to spiritually empower oneself. As life continues within the concentric energies of mantra, the user will be able to discern subtle variations in power and will be able to duly respond.

The mantra's force is multiplied exponentially if it is uttered with complete focus and concentration upon the task in a meditative fashion. Even though, simply uttering the words in an ignorant manner do bring about shifts in consciousness, the results are always limited. When we chant with pure hearts, we manifest the unseen and the unheard (the forces of the universe, cosmic energy, God, good vibes whatever you wish to call It).

Mantra is the manner to directly connect with that power and that fact has been recognized since time immemorial, when words were used not just to convey a particular literary meaning as they do today but to specifically manifest a force of nature, a heightened state of consciousness, a connection with the divine simply uttering the Word would draw this force out into our world.

A mantra is a sound vibration. The word "mantra" is an ancient Sanskrit word consisting of two connotations: man (mind) and tra (deliverance). A mantra is essentially a sonic vibration that delivers the mind from its material inclinations and spells of illusion.

Chanting is the process of repeating a mantra.

Chanting mantra does not require any previous qualification, initiation or knowledge to do so. It is actually one of the accessible meditative practices to engage in. Thankfully, it is not necessary to possess a lovely, sonorous singing voice. Therefore, it is not about how good we sound but about the sound vibrations we emanate and the underlying intention we bring to the practice.

I have found that mantra works on a number of levels. On a purely physiological level, the vibrations help to restore harmony to the organism. If you have finished chanting and you do not feel better physically, then there is something wrong with you. It is important to realize that mantras are beyond the ken of the simple arrangement of letters into a word the word itself being but a mere representation of something far more profound.

What is more significant in the cosmic order of things is the power that has been infused into each mantra. Mantras are not communicative in the sense that we have come to understand communication. First and foremost, the vibratory effects of a mantra invoke particular forces that leave a most discernible aftermath upon an environment.