When King Yayati, afflicted by old age, turned to his sons for help, he first addressed Yadu, his eldest born of Devayani. "What need have we to assist you with our youth?" Yadu replied, unwilling to take on his father's burden. Yayati then spoke to all his sons, "Take my old age upon yourselves, so that with your youth I may still pursue enjoyment. Through long sacrifices and the curse of the sage Ushanas, my desires are not yet fulfilled; I am unsatisfied, my sons. Let one of you restrain this old age with your own body, so that I, renewed, may once more delight in youth." Yet, none of them—beginning with Yadu—agreed to accept their father's old age. Disappointed, the royal sage Yayati cursed those four sons, as tradition recounts. But Puru, the youngest and steadfast in truth, came forward and said, "Do not give me old age; let me be happy with youth and a new body." Still, out of obedience and devotion, he declared, "I will take your old age and remain in the kingdom by your command." Yayati, relying on his ascetic power, then transferred his old age to his noble son Puru, and by Puru's vigor, the king was restored to youth. With Puru's youth, Yayati ruled the kingdom and remained undefeated for a thousand years. Still, even after all this time, his desires were not satisfied. He addressed Puru, "Through you I have obtained an heir; you are the maker of my lineage, my son. The lineage of Puru will attain fame in the world." Thereupon, that foremost of kings consecrated Puru as ruler of the kingdom. After a long time, Yayati reached the end destined for all. Now, I will recount the noble lineage of Puru—listen, O best of sages—for from this line were born the Bharatas, enhancers of the Bharata dynasty. But why did the lineage of Puru attain supremacy on earth, while the line of Yadu, though eldest, declined in prosperity? O Suta, narrate in detail another account of Yayati’s deeds, which is virtuous, life-giving, and praised even by the gods. This very question was asked long ago by Shatanika to Shaunaka: to hear the great account of Yayati, virtuous, pure, and life-giving. Yayati, eldest among us, was the tenth descendant of Prajapati. How did he obtain the exceedingly rare daughter of Shukra? O possessor of austerity, I wish to hear this from you in detail. Please recount, in order, the kings who held the lineage of Pururavas. Yayati was a royal sage, his splendor equal to Indra, the king of the gods. In former times, Śukra and Vṛṣaparvan gave him their daughters, as it happened. Now, as you ask, O best of kings, I shall tell you of Yayati, son of Nahusha, and his union with Devayānī. Once, a great conflict arose between the gods and the asuras throughout the three worlds, involving all beings, moving and unmoving, for the sake of sovereignty. Desiring victory, the gods chose a sage of the Aṅgiras lineage as their priest for sacrifice, while the asuras chose Kāvya Uśanas, also known as Śukra. Those two Brāhmaṇas, fiercely rivaling each other, were present in that battle. The gods, with their priest, slew the assembled Dānavas. But Kāvya, relying on the power of his knowledge, revived the asuras, and they rose up to fight the gods once more. When the asuras killed the gods in battle, Bṛhaspati, the gods' priest, did not revive them, for he did not possess the knowledge that mighty Kāvya knew: the science of reviving the dead. Thus, the gods fell into deep despair. Distressed by fear of Kāvya Uśanas, the gods approached Kaca, the eldest son of Bṛhaspati, and spoke: "Join with us, support us, and render the highest assistance. That knowledge resides in the Brāhmaṇa of immeasurable brilliance. Quickly obtain it from Śukra. You shall receive a share of the offerings. That Brāhmaṇa dwells near Vṛṣaparvan; you, O twice-born, are able to see him. He protects the Dānavas there, but does not protect the non-Dānavas. No one but you is able to propitiate him. Devayānī, his beloved daughter, is there. No one but you is able to win her favor. By virtue, generosity, sweetness, good conduct, and self-control, when Devayānī is pleased, you will surely obtain that knowledge." Thus sent by the gods, Kaca, son of Bṛhaspati, said, "So be it," and set out to the presence of Vṛṣaparvan. Honored by the gods, he swiftly went and, reaching the city of the lord of the asuras, bowed to Śukra and spoke: "O revered one, I am the grandson of the sage Aṅgiras, the direct son of Bṛhaspati, and known by the name Kaca. Please accept me as your disciple. O supreme teacher, I wish to practice the highest celibacy under you; please permit me, O Brahman, for a thousand years." Śukra welcomed him: "Kaca, you are most welcome; I accept your words. I shall honor you, the worthy one, and may Bṛhaspati be honored as well." Kaca, having replied, "So be it," accepted the vow, as instructed by Śukra, son of Kavi. He undertook the vow and its period as stated, and served his preceptor and Devayānī, O Bhārata. He constantly attended to Devayānī, a maiden blossoming into youth, by singing, dancing, and playing music, thus pleasing her. He also delighted the Bhārgava girl with flowers, fruits, and errands, ever attentive to her wishes.