Mool Mantra is the very first Hymn that appears in the Sikh Holy Book called the Sri Guru Granth Sahib Ji. The English Translation of the hymn is given below:
The Mool Mantra
There is Only One God
Truth is His/Her* Name
S/he is the Creator, Perfect Protector, Without Fear, No Enmity, The First Entity, Without Incarnations, Self-perpetuating; With the Guru’s grace: Recite!
True in the beginning, True Through the Ages, True even now and says Nanak will be True in the future |1|
Ek Onkar is the start of the Sikh Mool Mantra and the first phrase of the Sikh holy book, the Guru Granth Sahib.
MANTRA or Mantar is derived from the Sanskrit words consisting of the root man- meaning "mind" and the suffix -tra meaning, "tool", hence a literal translation would be "mind tool".
For the mantra to be effective, great emphasis is put on correct pronunciation and the level of concentration of the mind on the meaning of the word or words that are recited.
The purpose to mantras is to deliver the mind from illusion and material inclinations and to bring concentration and focus to the mind.
This part of the MoolMantra, Aad sach...Nanak hosee bhee sach, invokes the shakti power in the reciter, activates the kundalini (the latent consciousness or potential energy in the being), expanding ones horizon and giving one the power of Infinity.
The secret in the MoolMantra is that you must not break the breath, but break the sound, between ajoonee and saibhang.
The greatest effect from the MoolMantra occurs when it is recited all in one breath.