This is the appearance anniversary of Lord Chaitanya Mahaprabhu (1486-1534), who is Radha and Krishna combined.
On Gaura Purnima, which is a full-moon day, devotees fast till moonrise, and people visit the temple to see the Deities of the Lord. The devotees present dramas and classes about Lord Chaitanya’s life and activities. The Deities of Gaura-Nitai receive new clothes, and the devotees engage in extra kirtan. At moonrise we serve a prasadam feast (sanctified vegetarian food).
Chaitanya Mahaprabhu is the Supreme Personality of Godhead, Krishna Himself, appearing as His own devotee, to teach us that we can gain full enlightenment simply by chanting the holy names of the Lord:
Hare Krishna, Hare Krishna, Krishna Krishna, Hare Hare, Hare Rama, Hare Rama, Rama Rama, Hare Hare
Lord Chaitanya affirms that anyone who chants the Hare Krishna maha-mantra—regardless of background or spiritual qualification—can develop their innate love for God and experience great spiritual pleasure. Lord Chaitanya also predicted that the chanting of the holy names of Krishna would spread all over the world, a prediction that was fulfilled by Srila Prabhupada.