Effect of mantras

The chanting of mantras creates an environment of positivity and sacredness. Mantras have an impact at the subtle level also. Our physical body is the gross body, while our subtle body is 1.5 times larger than the gross body. And the Karana Sharira or Causal body is a 1000 times finer and subtler than even the subtle body itself. So we have three kinds of bodies. When the subtle body constricts and becomes smaller than the gross body, then a person becomes restless and miserable. When the subtle body diminishes even further, then a person loses his mental balance and feels like committing suicide. This is the root cause behind suicides.
By the practice of chanting mantras, pranayama and meditation the subtle body grows larger in size and also gets strengthened. When the subtle body becomes strong then one appears normal (physically). And when the subtle body expands much more than its normal limits then one feels that he is soaked in bliss. And as the subtle body expands further, it becomes finer and finer and merges or becomes one with the Causal body – that is when one gets Moksha (liberation or salvation).