Durga saptshati has multiple mentions of Navdurga.
When Markandeya ji asks for Durga kavach mantra, Brahma ji describes nine form of Durga or Navdurga.
Shailputri / Parvati : fear and sorrow goes away by her darshan. Daughter of Himalaya.
Brahmacharini : who continuously seeks Brahma
Chandraghanta : Moon resides in who's Ghanta
Kushmanda : this warm ...
A mantra when obtained from a competent Guru purifies one's mind eventually leading to moksha. How does that work? Prolonged meditation leads to accumulation of spiritual energy. A Guru with such a storehouse of energy transfers a portion of his energy when initiating a disciple with a mantra. When a disciple repeats such a mantra his mind is purified by ...