Once upon a time, the king of Benares had no heir, but finding three eggs in a nest - an owl's, amynah's, and a parrot's - he brought them, and when they were hatched out, adopted the birds as his children, giving them the names of Vessantara, Kundalinī and Jambuka. When they had grown up in the houses of the courtiers who had charge of them, the king had them summoned one by one, and asked them for advice as to how a king should reign. Each admonished the king in eleven stanzas, and, at the suggestion of the admiring populace, they were given respectively the ranks of general, treasurer, and commander-in-chief. When the king died, the people wished to make Jambuka king, but, having inscribed rules of righteousness on a golden plate, he disappeared into the forest.
The story was related in reference to the admonitions delivered by the Buddha to the king of Kosala. The king of the past was Ananda, Kundalinī was Uppalavanā, Vessantara, Sāriputta and Jambuka the Bodhisatta (J.v.109-25).
The verses uttered by Jambuka are often quoted. E.g., J.i.177; vi.94.