Pind Sammelan or Spindi is a ritual performed in Hinduism on the 13th day of death of somebody. This ritual is performed to place the departed soul with the ancestors and God. It is believed that before the ritual the departed soul is a "preta" (evil), and after performing this ritual, the soul will become "pitar" (good) and will be included in the ancestors.
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Pind Sammelan Wikipedia(Text) CC BY-SA