This is one of the most powerful Mantras in the world.
Guru Nanak, the first Prophet of the Sikhs, uttered this to encompass the fundamental nature of the infinite super-consciousness inside each one of us.
It is the first verse of the Sikh Holy Scripture, Sri Guru Granth Sahib. I have given the English translation of the verse by Bhai Sahib Kirpal Singh Gill, a distinguished luminary.
It is the root mantra and when uttered in deep surrender, as in this video, it repels every other power and cleanses the place, the body, mind and soul.
You can close your eyes, relax and just hear it to in a deeply relaxed state even recite along.
It is the magic wand of the Divine, not specific to any religion, rather for the entire humanity.
Here is the youtube link