Pitru Puja :includes Tarpana ,and worship of ancestors up to the 12 generations from mother and father side Shastra recommends Pitru Tarpana .Even great acharyas did it . Since we touch topic of Tarpana let me mention that Tarpana should be also offered to the unintentionally or unconsciously killed animals by us.
When an individual is on the brink of death, the relatives should inform the Priest in order that priest can perform death rites, normally Ganga water is placed within the mouth of the departing person at time of death .
The Pitru Paksha puja commonly referred to as Pitru Puja is performed to the 12 generation of ancestors from both the Father’s and Mother’s side. The term ‘Pitru’ refers to the ancestors and therefore the Paksha is that the specific time when Hindus can perform Tarpana and food offerings for the ancestors. This ancient ritual has widespread significance in Hindu culture. Shastra recommends offering the food and water to Pitrus not only in Pitru paksha but at least once a month during Amavasya . Those who fail to perform the rituals are believed to remain without food and water in their afterlife.
Our ancestors have left their love, blessings, properties and many other possessions that really shape the present and future giving more security and strength. The Pitru Puja (only done by the male members of the family) is sort of a Thanks giving procedure to point out respect and food offering to the ancestors for what they have left for the future generations and us.
Story of King Karna of Mahabharata
King Karna, the Son of God in Mahabharata was famous for his generosity and charity towards the poor. He used to give gold and money in charity every day after taking bath in the river and offering prayers to the Sun. After his death, Karna was offered food made from gold in Heaven. When he asked about the matter, God Indra told him that he gave only wealthy possessions to the poor and not food or water to anyone or his ancestors throughout his life. Upon this, Karna realized his fault and was eager to mend the wrongs. As per the decision of God, Karna was allowed to return to the Earth for the next 16 days to offer food and water to the poor.
The duration of 16 days that Karna was on Earth for feeding the people in need is termed as Pitru Paksha. According to the Hindu Mythological beliefs, during this is the time of the year the male members perform rituals offering food and water to the ancestors. The Pitru Puja is vital for eliminating Pitru Dosha and achieving blessings for the whole family. The duration isn't a positive time for any starting any new work or otherwise.
The Pitru Paksha starts on the complete moon day (Purnima) before the start of the Durga Puja in Bengal. The duration (also called Mahalaya Paksha) of 16 days of this paksha ends on the no moon day (Amavasya) or the Mahalaya tithi when the Durga Puja begins. It is also believed that Hindus shouldn't cut their hair during the Pitru Paksha. The period should also be avoided for doing any new work or beginning something important.
In Shastra, there's a mention of performing Pitru Puja on every new phase of the moon day for all 12 months of the year. However, due to hectic schedules, this may not be possible for many people. The family priests therefore suggest performing the Tarpana puja by offering rice with sesame seeds and water a minimum on the religious holiday of Mahalaya Amavasya.
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