As a rule the only mantra used in this sadhana is that of the Mother or of my name and the Mother. The concentration in the heart and the concentration in the head can both be used—each has its own result. The first opens up the psychic being and brings bhakti, love and union with the Mother, her presence within the heart and the action of her Force in the nature. The other opens the mind to self-realisation, to the consciousness of what is above mind, to the ascent of the consciousness out of the body and the descent of the higher consciousness into the body.
OM is the signature of the Lord.
OM is the syllable, OM is the Universe; the past, the present and the future,—all that was, all that is, all that will be is OM…. Likewise all that may exist beyond the bounds of Time, that too is OM.