ity uktva nahuso jayam
tadiyam purave vayah
dattva sva-jarasam tasmad
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sukadeva Gosvami said: After speaking in this way to his wife, Devayani, King Yayati, who was now free from all material desires, called his youngest son, Puru, and returned Puru’s youth in exchange for his own old age.