Repetition of mantra, called japa, calms the thoughts, gives the mind a focus and leads us to our inner Self, our consciousness. The mantra is often the name of the divine, like Rama, or it is a universal word like om (the sound of the universe) or sohum (the sound of the breath). These sounds are a powerful way to align ourselves with the energy of the universe, and the internal vibration from the navel to the throat connects the physical body, the mind and the spiritual Self. The repetition of a mantra also activates the parasympathetic nervous system, by which the heart rate slows down and we therefore enter a state of relaxation.
Japa can be done with awareness and full concentration but can also be done in idle times when watching something or commuting. It gives you access to a constant uplifting force. Paramhansa Yogananda explained that japa attunes the radio of our consciousness to positive, uplifting and God-reminding thought patterns. It spiritualises daily life.
Try if you can to chant these sounds and mantras out loud and observe the sounds vibrating in your own eardrums and in your body, feel the reverberations of those vibrations and sense the calming energy that seeps through the being during this time. If the mind wanders, let it, observe it, be aware of it, and bring it back to the mantra. Over time, the mind will be filled with a sense of emptiness.
Extracted from Prajna: Ayurvedic rituals for happiness by Mira Manek