It is Lord Shivas wedding today with Ma Parvati do you know why we keep fasting today? It is because the people of Brides family take food only after Kanya Daan..and that happens late in Night we are from Ma Parvtis side in this wedding because lord Shiv had all the Ghosts in his Baraat ..how beautiful and innocent are the thoughts and rituals of our religion what do you feel?
No, sir.....today is not the wedding day of lord SIVA & PARVATI......Sital sasthi (jaistha sukla sasthi-21day of jaistha ) is the wedding day of Lord SIVA.......the story is.....when Dakshya prajapati refused to invite his son-inlaw(SIVA) to the auspicious yagyan then his daughter SATI(wife of Lord siva) felt offended and imolate herself.....when SIVA heard the news he came and started the TAANDAB with the dead body of Mata SATI on his shoulder..........when it continued for a longer time.....then Lord Vishnu planned and Mata PARVATI took birth from the womb of MAINA and the father was , the king of Mountain HAIMAVAH.......narad came and informed to lord siva that Devi SATI took birth as PARVATI at HIMALAYA(Kailash)......then lord SIVA calmed down........on this day, married women keep fast in a desire that , their husband should love them like lord SIVA........this is the story what i was told and collections are with me....
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Siva is auspiciousness. Maha shiv is also Sada Shiv meaning eternal auspiciousness. He is also Nirguna meaning "without attributes" He is also Digambara - Dik + Ambara meaning "Space/sky/directions as clothing". All such stories are lores told in those days to impart education. Every story had a moral. Fasting and feasting are being practised by every religion and sects.