The world exists only in awareness. Consciousness is awareness. Nothing exists that is not manifestation of Universal consciousness or awareness. Shiva and Shakti are the manifestations of Supreme Consciousness. Shiva is Nirguna, but is visible from his power which is Shakti. The power or energy of Shiva is Shakti. Shakti is inseparable from Shiva in a manifested Universe. Shakti is the fragrance of the flower, rays of the sun and heat of the fire. This Shakti is what we name as Goddess Durga.
Adi Guru Shankaracharya says:
आत्मा त्वं गिरिजा मतिः सहचराः प्राणाः शरीरं गृहं
पूजा ते विषयोपभोगरचना निद्रा समाधिस्थितिः ।
सञ्चारः पदयोः प्रदक्षिणविधिः स्तोत्राणि सर्वा गिरो
यद्यत्कर्म करोमि तत्तदखिलं शम्भो तवाराधनम् ॥४॥
O Lord, You are my Atma (Soul), Devi Girija (the Divine Mother) is my Buddhi (Pure Intellect),
the Shiva Ganas(the Companions or Attendants) are my Prana and my Body is Your Temple,
My Interactions with the World are Your Worship and my Sleep is the State of Samadhi (complete absorption in You),
My Feet Walking about is Your Pradakshina (Circumambulation); all my Speech are Your Hymns of Praises,
Whatever work I do, all that is Your Aradhana (Worship), O Shambhu.
Durga, the Divine mother is the power behind the existence of the whole universe. It is She that manifests the Universe into existence, and is the doer of all actions. She is both Matter and Mind. She is Prakriti that is the manifestation of entire physical world. In Devi Mahatmaya – a Hindu text on goddess Durga – it is stated that Durga is the earth itself, and therefore a Universal mother who nourishes and sustains all living beings. In each living creature, She manifests as that energy that procreates, sustains and gives each species a unique identity. She is also the Maya, the delusional energy that makes an individual think of himself as separate from the Universal Consciousness. An individual can experience the state of expanded consciousness only when the divine Shakti meets the Shiva within. This process is catalysed only by Her Divine Grace and blessings.
Goddess Durga, the power and energy of the Universe expresses Herself as the three attributes of Nature namely Tamas (inertia and ignorance), Rajas (activity and dynamism) and Sattva (equilibrium and serenity). Maha Kali is her Tamsic Shakti that is the power of destruction. So she becomes the consort of Rudra, who by the strength of her destructive power destroys. Maha Lakshmi is her Rajasic Shakti or power of activity. So she becomes the consort of Vishnu who by her intellectual power sustains the Nature. Maha Saraswati is her Sattavic Shakti or power of equilibrium or transcendence. So she is connected to Brahma who by the grace of her creative force is able to create.
The nine forms of Durga, or Nav Durga represent the energies and powers of the nine Chakras in our body, from Muladhara to Sahasrara. This Navratri, let us invoke Durga of each Chakra to cleanse us of all our fears and bless us with all insights and lessons, so that our Shakti within, meets Shiva.