The Mahabharata

"yada yada hi dharmasya
glanir bhavati bharata
abhyutthanam adharmasya
tadatmanam srjamy aham" (Bhagwat Gita: Chapter Four verse 7)

"Sri Krishna said: Whenever and wherever there is a decline in virtue/religious practice, O Arjuna, and a predominant rise of irreligion—at that time I descend Myself, i.e. I manifest Myself as an embodied being."

"paritranaya sadhunam
vinasaya cha duskritam
dharma-samsthapanarthaya
sambhavami yuge yuge" (Bhagwat Gita: Chapter Four verse 8)

"Sri Krishna said: To deliver the pious and to annihilate the miscreants, as well as to reestablish the principles of religion, I Myself appear, millennium after millennium.

The Mahabharata symbolises the eternal battle between the forces of Dharma- righteousness and Adharma- asuric tendencies.It is narrative of a period when Asuric forces were threatening to overwhelm the world and only a divine intervention could have saved the situation.
The Pandavas and Kauravas are descendents of Kuru,king of Hastinapur. Yudhistir,the eldest of the cousins is the natural heir to the throne but due to the intrigues of Duryodhana,he and his younger brothers,Arjuna,Bhima,Nakul and Sahdev along with their mother Kunti are forced to go into exile. Yudhistir,also known as Dharmaraj is supposed to have been a pillar of virtue and morality and adhering to the highest standards of his age.
Krishna,an incarnation of Lord Vishnu, sides with the Pandavas and repeatedly requests Duryodhana to see reason and give the Pandavas their rightful share of the kingdom.However Duryodhana remains adamant and tries to annihilate the Pandavas in many ways.
In the ensuing battle of Kurukshetra,the Pandavas with the support of Sri Krishna emerge victorious and the Kauravas are annihilated.

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