Mantras are not arbitrary compositions, but rather words imbued with spiritual power, revealed in the hearts of the seers of God, or rishis. The principal use of a mantra is spiritual. When the mantra is received from an experienced teacher and repeated for a long time with faith and love, it creates miracles in spiritual life. Japa purifies the heart's blemishes, purifies our unwelcome desires and passions, and opens the door to higher spiritual experiences.
— Swami Shraddhananda, Seeing God Everywhere by Swami Shraddhananda, Pravrajika Vrajaprana, editor