In the clan of Ishkvaku, founder of solar dynasty, Mahabhisha was born. He, with his undefeated prowess became the lord of the earth and with his intellect had gratified the celestials in the court of Indra. His intelligence was unmatched and later he attained heaven and became the royal sage among all the Brahmanas in the courtroom of Sakra. One day when all the royal sages and Mahabhisha were performing the rituals for great sire Brahma, the queen of rivers Ganga also came to pay her adorations. As she enters, her clothes got displaced due to winds, leaving her uncomfortable in front of the sages. All the sages bent down their heads but Mahabhisha couldn’t control his emotions and continued staring at the uncomfortable queen of rivers. The emotions just cruised across, but it was no right in front of the ascetics and for Mahabhisha who had attained the place after abstaining himself from the sensual desires. But that was the different day and the damsel had stolen the ascetism of the royal sage. Seeing the uncontrolled desires of Mahabhisha, the Brahmanas present there cursed him that he had to reborn on the earth and after completing one more cycle of human life would come back. Ganga was also cursed to be born in the human race for one cycle.
Daksha had a daughter called Surabhi who got impregnated with Rishi Kasyapa and gave birth to a daughter who later was transformed in the form of a cow, Nandini to benefit the people on earth. The cow was given to Rishi Vashistha who had his hermitage on the mountain Meru.
One day the eight Vasu brothers were roaming around the earth with their wives on their celestial chariots. They crossed the hermitage of Rishi Vashishtha where they saw Nandini. The wife of youngest Vasu Dyu got allured with the cow and she expressed her desire to take that cow for her friend. She knew that the cow had all the heavenly qualities and its presence only can free the people from decrepitude. She asked her husband Dyu to steal the cow and take away with them. Dyu also knew the qualities of the cow and surrendering before the adamancy of his wife he took the cow and they flew away from the hermitage. Vashishtha when came to know about this unethical behavior of the Vasus, summoned them and cursed all of them to born on earth as human once. Vasus were ashamed of their act and they begged for the mercy. Considering it was venial act, Vashishtha gave them the option to choose their mother on the earth and told that seven of them can live on earth for one day only but Dyu who had stolen the cow had to complete his human life cycle.
Vasus under the curse of Vashishtha started looking for a lady with the celestial powers who could have the brothers in her womb. While searching they encountered Ganga who was cursed by Brahmanas to born in the human race. The fate of Vasus and Ganga matched and when Vasu brothers requested Ganga to accept them as their sons in human form, she agreed. Vasus also asked her to kill the sons as soon as they would born so that they wouldn’t have to live in human form. Ganga accepted but mentioned that she would want one son from her husband to live his full life.
Ganga incarnated herself as demoiselle and came on earth with the desire to find the man with great prowess and who could marry her on her conditions. Years passed and one day Ganga saw Pratipa, the descendant of Kuru dynasty, while he was in his meditation on a river side. Ganga came near to Pratipa and expressed her desire to become his wife. Pratipa mentioned that he could not accept her as his wife but promised that if his son would born, he could accept Ganga as her daughter-in-law for his son. Ganga accepted and went away. Pratipa also returned to his kingdom and days passed. Pratipa begot Shantanu.
Shantanu ruled the Kuru dynasty for years and his caliber was no less than the Indra himself. He had expanded his kingdom to large range and during his reign the flora and fauna flourished fearlessly. Shantanu was also addicted to hunting and one fine day while on hunt he encountered the maiden with spotless beauty. She was none else than Ganga. Shantanu’s desires overgrew and he wanted Ganga to be her queen. Ganga was suffering from the curse of serving a wife of a human but also had to fulfill the promise made to Vasus. Hence, she put the condition on Shantanu that she would accept him as her husband only if he promises that he would never ask her about the actions or decisions she would take. Shantanu arrested by the divine beauty of the damsel couldn’t say no and accepted her as his wife. Days passed and Ganga gave birth to seven sons of Shantanu, whom she eventually killed as per the promise to Vasus and Shantanu under the oath given to Ganga couldn’t ask her the reasons. When the eighth son was born, Shantanu couldn’t control his fatherly emotions and stopped Ganga from slaying the son.
Ganga told that as he stopped her and broken the promise, she would not stay with him and would leave for the place from where she came. Shantanu left with no choice had to let Ganga go with the eighth son whom they name Devvratta. But Ganga promised that she would return his son once he attains the adolescence.
Shantanu was no other than the reincarnation of Mahabhisha, who lustfully stared at Ganga during the adorations. Devvratta was incarnation of Dyu who stole the cow surrendering himself before the adamancy of his wife. Dyu was also cursed to stay as ascetic in his reincarnated life and had to live the entire life facing all the menaces.
Devvratta was later called as Bhishma who lived the life of an ascetic serving the kingdom as a caretaker because of the curse in his previous life. The bliss in the life is acquired by the deeds and so the agony.