On the full moon day, in the month of Jyestha, a very sacred festival known as Devasnan Purnima or Snana Yatra is held for Lord Jagannath. It is said that one’s sins are washed away fully if one gets darshan of the Lord on this day of the bathing festival. According to the Skanda Purana when King Indradyumna installed the wooden deities he arranged this bathing ceremony. Hence, this festival is celebrated to commemorate the Appearance of Lord Jagannath – the Lord of the Universe.
After Snana Yatra, the deities are believed to fall ill with fever and do not return to their pedestal. On the 16th day, the Deities after complete recuperation become ready for public view. This first appearance of Lord Jagannath for his devotees is called 'Netrotsava' (festival for the eyes) or 'Nava Yauvanotsava' (festival of the ever-fresh and always youthful Lord).