Durga Saptashati
Durga Saptashati or Chandi is  from Markandeya Purana. It is a composition of Slokas or verses on the glory of  the Divine Mother. Hence it is also called Devi Mahatmyam.The whole text is  divided into 13 chapters consisting of 700 Slokas. Therefore its title is Saptashati.  The entire text is considered by  some as one single Mantra. There is another opinion that the name should be Saptaśati as it deals with the story of seven Satis or "pious persons". The  seven mothers are Brāhmi, Māheśwari, Kaumāri, Vaisnavi,  Vārāhi, Indrāni, and Cāmunda. Three  aspects of the Divine Mother have been depicted in this work. They are-

  1. Mahakali (Chapter 1)
  2. Mahalakshmi (Chapters II to IV) and
  3. Mahasarasvati (Chapters V to XIII).

These aspects are narrated briefly  as follows.

1. Mahakali (Chapter I)
Chapter I starts with the  meditation of the Divine Mother giving a brief description of her form and  points out that Brahma extolled her in order to destroy the two Asuras, Madhu  and Kaitabha, when Vishnu was in mystic sleep.

It then narrates the story of a  king, who lost his every thing like kingdom, name and fame due to his  evil-minded ministers and other enemies and that of a wealthy merchant who was  thrown out of his house by his own wife and sons due to their greed for his  wealth. Both of them took shelter in the hermitage of the sage Medhas. Despite  the peaceful environment of the hermitage, both the king and the merchant  remained always dejected thinking about their worldly belongings left behind  and the very same persons who were ungrateful, unloving and who caused them  wrong not knowing the reasons for their attachment to them.

Sage Medhas explains to them that  this attachment is due to Mahamaya who makes the existence of the world  possible with all its dualities. Mother Bhagavati, Mahamaya, forcibly drawing  the minds of the even wise, throws them into delusion. This Mahamaya is also  the Yoganidra of Vishnu, the Lord of the world.

In this context the sage Medhas  recalls the tale of destruction of the two Asuras, Madhu and Kaitabha, by the  Lord Vishnu with the help of Shakti, the Mahamaya. During the mystic slumber of  the Lord two Asuras, Madhu and Kaitabha sprang up and threatened to kill Brahma.  Seeing these two fierce Asuras and Vishnu in slumber, Brahma worshipped  Yoganidra to awaken Him
  .
He described her in several  wonderful terms such as incomparable Goddess of Vishnu, Yoganidra; the queen of  cosmos; the cause of the origin, sustenance and dissolution of the Universe in  the forms of creative, protective and destructive powers etc. She was referred  to as Qmkara, Savitri and the source of three gunas, having a form more  pleasing than all the pleasing things and the Supreme Ishwari. After eulogizing  her thus, Brahma implored the Mother to charm the two Asuras with her superior  powers and let Vishnu. awakening from His sleep and rising up to his true  nature, slay them.

To awaken Vishnu, the Dcvi of  destruction drew herself out from 1otus eyes. Vishnu got up from His Yoganidra  on the Universal Ocean and started to fight with Madhu  and Kaitabha. While the fight between Vishnu and the two Asuras was going on,  deluded by Mahamaya, the Asuras told Vishnu to ask a boon from them. Vishnu  replied that if they were satisfied with Him, they should be slained by Him  then and there. The Asuras replied that they were prepared to be killed by  Vishnu ‘where the earth is not flooded with water’. Vishnu took them on His  loins which were above the water and severed their heads with His discus. Thus  Mahamaya herself appeared when praised by Brahma to become an instrument for  the killing of the two Asuras.

2. Mahalakshmi (Chapters II to IV)
Chapter II starts with the  meditation of Mahalakshini as a destroyer of the demon Mahisasura giving a  picture of her beautiful form.

The legend of the killing of  Mahisasura is then described. In a war between Devas and Asuras, the latter  defeated the former and their Lord Mahisasura became the Lord of Heaven in  place of Indra. The Devas led by Brahma went to Shiva and Vishnu and complained  about the atrocities being perpetrated by the Asuras under their master  Mahisasura.

Having heard the misdeeds of the  Asuras, a great stream of light issued out of Vishnu. So also from Shiva,  Brahma, Indra and other Devas. All this light came to be concentrated into one  huge mountain of flames permeating all the three worlds with its luster and  then it assumed a female form. Looking at her the immortals who were oppressed  by Mahisasura experienced joy unending. All the Devas gave her several martial  weapons as offerings.

Mahisasura responded to this  situation with wonder and rushed towards that female form.
He saw Dcvi pervading the three  worlds with her radiance. In the battle that followed between Dcvi and the army  of Mahisasura, the latter was completely wiped out. Here Dcvi is referred to as  Chandika, Ishwari and Ambika.

Chapter  III describes the intense fight between Chandika and Mahisasura. The Chandi  says ‘Chandika jumped and landed herself on that great Asura, who assumed the  form of a buffalo and pressed him on the neck with her foot and struck him with  her spear. Thereupon, caught up under foot, Mahisasura partially resumed his  real form. Fighting thus with a half—revealed form the Asura was killed when  Dcvi struck off his head with her sword.

Chapter IV contains the  propitiation of Devi by the Devas in the most flowery terms. This Chapter in  the original Sanskrit text is very sweet in language and highly sublime in  content. Here Dcvi is referred to as Bhadrakali and Gauri. She is  Mahisasuramardhini,

3.  Mahasarasvati (Chapter V to XIII)
Chapter V starts with the  meditation of Mahasarasvati praising her incomparable form and alluding her as  the substratum of the three worlds and the destroyer of Asuras like Sambha and  others. The two Asuras, Sumbha and Nisumbha defeated the Devas like Indra.  Vayu. Agni etc. and took away their authority and functions.

The Devas, hailing the Divine  Mother lavishly, begged her to destroy the Asuras who were the source of their  calamities. Hearing the glorious hymns addressed to her, Ambika came out of  Parvati’s physical sheath. Hence she is called Kausiki and Parvati is called  Kalika.

Chanda and Munda who are the  servants of the two Asuras happened to see Ambika’s beautiful form. They  requested their masters also to see her. Acceding to their request, the two  Asuras sent a messenger to Ambika for fetching her to their court. Ambika  reacted to the messenger saying that whoever conquers her in the battle would  be her husband. Then followed the battle between Ambika and the Asuras.

Chapter VI deals with the slaying  of the Asuras Chieftain. Chapter VII describes the killing of Chanda and Munda  by Ambika. Her name Chamunda is derived from this incident. Chapter VIII  details the killing of another Asura by name Raktabija by Ambika. Here she is  called Kali. Chapter IX explains the slaying of Nisumbha by Kali while Chapter  X portrays the slaughter of Sumbha. Chapter XI contains the eulogy of Devi by  all the Devas on her victory over the Asuras. Here She is referred as Narayani.  Gauri, Durga, Brahmani. Her various attributes are then expounded. This Chapter  is of very high lyrical excellence. It is really a pleasure to chant these  verses. Chapter XII presents us with the merits that will go to anyone on  reciting the hymns of Devi Mahatmyam. Chapter XIII concludes the Saptashati  saying that Devi disappeared after granting boons to the king and the merchant  who started the dialogue with the sage Medhas which resulted in the exposition  of Durgasaptashati.