Nityananda Trayodasi is the appearance anniversary of Lord Nityananda. Lord Nityananda, whose name means “eternally blissful”, is the brother of Lord Caitanya. They are traditionally worshipped together, as are Krishna and Balarama.
Nityananda Prabhu appeared as Chaitanya Mahaprabhu’s principal associate for spreading the congregational chanting of the holy names of the Lord. He appeared in 1474 in the village of Ekachakra, now in West Bengal.
On Nityananda Trayodasi devotees fast till noon. The day is spent recounting the special glories of Lord Nityananda, or Nitai as He is sometimes known, and in vigorous kirtana. In temples there is a ritual bathing of Gaura Nitai deities.
“As Lord Nityananda is eternal, hence His lotus feet are also eternal and anyone who takes to the service of Lord Nityananda, (s)he also becomes eternal.”- Srila Prabhupada