Shri Dus Mahavidya
The ten great learnings are related with Sati, Shiva and Parvati, all synonymous of the same Shakti (power). She is also known as Nav Durga, Chamunda, Vishnupriya etc and is worshipped. The origin of this ten great knowledge is as follows.
Daksha Prajapati, the father of Sati, once performed a religious sacrifice (Yagya) in which he invited all the deities and sages, except his own Son-in-law lord Shiva, because of his jealousy towards him.
Sati wanted to be present at that occasion but Lord Shiva refused to give permission, thinking it was improper for her to go without the invitation. But she was unmoved: She said "I will certainly get to the Yagya performed by Daksha Prajapati, I would either get the fortune of that religious sacrifice for my dearest, deity of the deities, and husband or else I would destroy that religious sacrifice itself."
Sati's eyes became red. She looked at Lord Shiva violently, her lips began to flutter, and her complexion became dark. The fire of her anger made her appearance look frightened and violent.
Such an appearance of Sati was frightening even for Lord Shiva. Her appearance, which had the blaze and radiance of crores of mid-noon-suns, made her so fearful that he just ran away.
To stop Lord Shiva from running away in all the possible ten directions, Sati manifested herself in to ten different forms. These ten Shaktis (powers) of Sati are known as the ten great knowledge's.
(1) KALI (2) TARA (3) SHODASHI (4) BHUVANESHWARI (5) TRIPURSUNDARI (6) CHHINNMASTA (7) DHOOMAVATI (8) BAGALAMUKHI (9) MATANGI (10) KAMALA
Among all the ten great learning’s, Kali is the main. All the other nine are nothing but the violent and somber appearances of Kali. These ten appearances of Mahakali are called the ten great learning’s. These are considered as the powers of Lord Shiva, the Lord of all the knowledge’s. Though these ten great learning’s are worshipped in many other forms and appearance, but these ten forms mentioned above are the main.
The method of worship of all these ten forms is different. KALI, TARA, CHHINNAMASTA, BAGALAMUKHI AND DHOOMAVATI are apparently violent but in reality they are most merciful, where as BHUVANESHWARI, SHODASHI, TRIPUR, BHAIRAVI, MATANGI and KAMALA are the somber appearances. These ten great learnings are the most valuable wealth of the Sadhakas (accomplishers), which give infinite accomplishments and also are capable of introducing the infinity to them.
The last chapter of todala Tantra equates Vishnu's ten incarnations with the ten Mahavidyas as follows:
"Shri Devi said: Lord of Gods, Guru of the universe, tells me of the ten avatars. Now I want to hear of this, tell me of their true nature. Paramesvara, reveal to me which avatar goes with which Devi.
"Shri Shiva said: Tara Devi is the blue form, Bagala is the tortoise incarnation, Dhumavati is the boar, Chinnamasta is Nrisimha, Bhuvaneshvari is Vamana, Matangi is the Rama form, Tripura is Jamadagni, Bhairavi is Balabhadra, Mahalakshmi is Buddha, and Durga is the Kalki form. BhagavatÌ Kali is the Krishna murti." (Todalatantra, chapter 10)
The worship of these is also prescribed as an astrological remedy - for the 9 planets and the Lagna as follows:
Kali for Saturn, Tara for Jupiter, Maha Tripura Sundari (or Shodasi-Sri Vidya) for Mercury, Bhuvaneshvari for Moon, Chinnamasta for Rahu, Bhairavi for Lagna, Dhumavati for Ketu, Bagalamukhi for Mars, Matangi for Sun, and Kamala for Venus
“Kali Tara Mahavidya Shodashi Bhuwaneshwari, Bhairawi Chinnmasta ch Vidya Dhumawati tatha. Bagla Siddhividya ch Matangi Kamlatmika, Ayeta Dusmahavidya Siddhividyah Prakirtitah.”