The Obon Festival is a Japanese Buddhist three-day observance during which families honor their deceased ancestors. According to scholar and Shin priest Alfred Bloom,
The Obon observance has deep roots in Asian ancestor cults from India to Japan. It is based on the legend of the monk Mogallana's rescue of his mother from the hell of hungry ghosts. The story dramatizes the son's anxiety for his mother's welfare after her death and how it was resolved through Buddhist practice.
Practicing meditation, Mogallana gained spiritual insight and vision, which enabled him to see his mother's true condition. He then asked the Buddha how to free her from her suffering.