The Bodhisatta was once a king’s advisor. The full account of this lifetime is told in the Vidhurapandita Jataka (#545) while the Catu-Posathika Jataka only relates this single incident from that story.
Four great kings – Indra, king of the gods; a naga king; a garuda king; and the Bodhisatta’s king – were friends in their previous lives and one day after keeping the holy-day fast and meditating they sat down to chat. Indra wondered what their greatest virtues was. The naga king said he had great patience: the garuda are the mortal enemies of naga, but anger never arises in him when he sees one. The garuda king said he possessed great self-restraint: naga are the garuda’s chief food, but he remains hungry rather than kill and eat one. Indra said he kept great abstinence from desire: he left behind the glory of heaven, where every sort of happiness can be found, and came to Earth to focus on the holy day. The human king said he maintained great devotion to religious perfection: he went to his park to observe the holy day instead of going to his harem, which had sixteen thousand dancing girls.
Each felt their virtue was superior to the others, so they went to the palace to ask the Bodhisatta which of them was the greatest. After all four kings shared their stories of virtue, the Bodhisatta declared them equal, like the spokes of a wheel. All greatly pleased with this answer, they praised the Bodhisatta’s incomparable wisdom and gave him gifts: a robe made of heavenly silk (Indra), a golden garland (the garuda king), a jewel (the naga king), and one thousands cows (the human king).
In the Lifetime of the Buddha
One day some of the Buddha’s disciples were discussing his supreme wisdom. In particular, how he was so quick-witted he crushed his opponents’ arguments, even reducing revered sages to silence. When the Buddha heard them talking about it, he said it was no big deal that he could convince others because he had reached enlightenment. Then he told them this story so they knew he’d been able to do the same in the past too.
Indra, the naga king, the garuda king, and King Dhananjaya were earlier births of Anuruddha, Sariputta, Moggallana, and Ananda, four of the Buddha’s top disciples.