Question: I am chanting mantra when i am free and also in job. i.e my one part of internal mind will be chanting and other part will be doing my job and in between also the mantra goes on in my mind. Will the effect be the same? Can u please clarify on this?
Yes effect will be same. This is called Ajapa-japa.. silent chanting throughout the day.
Japa (or japam) means repeating or remembering a mantra (or mantram), and ajapa-japa (or ajapajapam) means constant awareness of the mantra, or of what it represents. The letter A in front of the word japa means without. Thus, ajapa-japa is the practice of japa without the mental effort normally needed to repeat the mantra. In other words, it has begun to come naturally, turning into a constant awareness. The practice of constant remembrance evolves in stages:
At first, you intentionally repeat the syllables of the mantra internally, as if you are talking to yourself in your mind. You allow the inner sound to come at whatever speed feels comfortable to the mind. Sometimes it is very slow, as if the mind were wading through a vat of honey. At other times it is very fast, as if flying through the sky without restraint.
With practice, the mantra japa is repeated automatically, like a song that you have heard many times, which just comes on its own. (Some practitioners consider this automatic repeating to be the meaning of Ajapa-Japa, though there is a subtler meaning, as described below.)
Gradually, you merely remember the mantra with attention drawn to it. It is more like noticing what is already happening, rather than causing it to happen. It is somewhat like the attention stance of listening rather than speaking, though you might not literally hear the sound.
In time, the feeling of the mantra is there, even when the sound or remembering of the syllables is not there. For example, sometimes people will say, “OM, Shanti, Shanti, Shanti,” where the word Shanti means peace or tranquility. During the remembering of the word there may be two things—the word and the feeling of peace or tranquility. When the syllables fade away, the feeling may still be there; this is remembrance of the feeling of the mantra.
As the practice evolves, there comes a pervasive awareness of the mantra, subtler than both the syllables and any surface level meaning or definition. This constant awareness is the meaning of Ajapa-Japa of the mantra.