The Goddess Kali is one of the main deities of the practice of Yoga. She represents the reabsorption of the time bound universe back into its eternal source. She governs over the process of mergence. She is the power through which earth is dissolved into water, water into fire, fire into air, air into ether, ether into mind and mind into pure consciousness. She represents the movement back through the Tattvas to the Purusha beyond them. She grants the highest strength, energy and vitality, but one must be strong oneself in order to carry her indomitable force. Kali relates to the great prana mantra Krim. It also occurs as three syllables -Krim Hum Hrim-or as seven syllables: Krim Krim Krim Hum Hum Hrim Hrim. Another set of three syllables for Kali is: Hrim Srim Krim! Kali grants the prana of eternity that can overcome all the negative energies born of time.
The Kali Bijas, Krim Hum Hrim, are powerful for Tejas, particularly in the root chakra and the heart.
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Such deities provide us with an intimate and personal connection with the Divine and our higher Self. Whether for spiritual or mundane purposes, a mantra is usually connected to the propitiation of the appropriate deity or aspect of the Divine for the purpose involved, like Lakshmi for wealth, Sarasvati for learning, Kali for strength, or Shiva for peace.
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Yet working with Kundalini, we must remember that Kundalini is a form of the Goddess. She is closely connected to Kali, the dark Goddess of Infinite Space who represents Kriya Shakti or the power of yogic action. Kali works to set in motion the inner process of Yoga or self-integration within us. This proceeds through the dissolution of our attachment to the external world. Through it the external world gets withdrawn into the tattvas or cosmic principles, taking us back step by step from the gross elements to the Purusha or pure awareness, the higher Self.
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Krim is the seed mantra of Kali, the Goddess of time and transformation, the consort of Lord Shiva, the Destroyer/Transformer in the Hindu trinity of great deities. Through it, we set Kali's power in motion within us. It serves to energize things to the highest level, which is to raise their level of vibration to the point where we can return to the source.
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Hum with a long vowel sound has a similar meaning but a more feminine and Shakti quality. It relates to fierce forms of the Goddess like Kali, Chandi and Chhinnamasta. It has the power to cut off and indicates the sword.
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Svaha is repeated after mantras at Yajnas (fire sacrifices) while one is offering grains or anything else into the fire. Yet it is also used after mantras that one wants to project more fire energies with, like Kali and Tara mantras.
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Combinations of these mantras can be used, particularly relative to deities, like the the Kali mantra Krim Hum Hrim to bring energy and light to all the chakras or the Sundari mantra Hrim Srim Klim to bring bliss and contentment.
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The three have masculine and feminine forms as Brahma/Sarasvati, Vishnu/Lakshmi, and Shiva/Kali. It is the feminine forms that are most connected to speech and mantra. Generally, the Goddess Sarasvati, who relates to knowledge and to creative power, is the main Goddess of speech, communication, poetry and music. But the other two forms of the Goddess also relate to speech in different aspects. Lakshmi is the loving or nurturing form of speech, speech at a devotional level. Kali is the energetic or transformative form of speech, speech at a pranic level. As indicating the power of Shakti overall, Kali reflects higher forms of speech in which the Divine Word awakens within us and withdraws us back into the Absolute, revealing the beauty and bliss beyond time and space.
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Sundari is a Goddess of love, beauty, delight and Soma. She is the deity of the mystic Moon which is also the energy of the crown chakra. Her grace is most sought after in the higher Yoga practices. She allows the immortal Soma nectar to flow from the thousand-petal lotus above, granting all higher powers of speech and mantra. Generally called Tripura Sundari or the "Beauty of the Three Worlds", she represents the benign aspect of Shiva's consort, whose fierce form is Kali.
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Durga represents the Great Mother in her protective role. She rides a lion and carries the weapons of the Gods and leads the army of the Gods to destroy all negativity. Worshipping her is one of the best places to begin to honor the Mother. Kali is often regarded as her fiercer manifestation.