A mantra or a religious chant is a vibratory frequency, which has the ability to raise the energy levels of the person doing the chanting or listening to them. If you chant the mantra it in its rightful tones and frequencies, it will lift your body simultaneously in the right zones. A mantra is a powerful pill of energy frequency and when chanted correctly it will lift your frequency.
Chanting a mantra does not require a belief system, no matter what, if you keep chanting the mantra you will get the benefits as it will raise your frequency.