There are three disciples with the name of Nanda: Nanda, Ananda, and Sundarananda. Nanda is known as “Nanda the Cowherd” because he watched cows when he was a lad.
Nanda’s name means “wholesome bliss.” As a cowherd, he heard the Buddha speak the Eleven Matters of tending cows, using the tending of cows as an analogy for cultivation of the Way; Nanda, realizing that the Buddha was possessed of all-knowledge, resolved to leave home and soon attained the fruition of Arhatship.
On one occasion the Buddha instructed Nanda to preach to a group of five hundred Bhikshunis. Hearing him speak, they all attained Arhatship. In the past, the five hundred Bhikshunis had been the concubines of a single king. The king, a great Dharma protector, built a large pagoda in honor of a Buddha. The concubines, believed in the Buddha and made offerings at the pagoda, vowing that in the future they would all obtain liberation with the king. The king was a former incarnation of Nanda