This fast is observed in many forms and for many benefits. It may be observed for the propitiation of the planet Shukra (Venus), and to ensure longetivity of the son, peace of mind and harmony in the family. It is also observed in the honor of goddess of white raiment's. It is a very popular fast, and is generally observed by the ladies to please goddess Santoshi Mata. Santoshi Maa is an other form of Parvati or Durga.The devotees wear white clothes on this day and eat white food, like kheer, only once at night. Sour dishes are avoided.
In good old days, there lived three friends. They belonged to Brahman, Baniya and royal families. They were fast friends. All the three were married but the Baniyas son had not brought home his wife after his marriage ceremony. One day, the three friends were together gossiping. They talked about their wives. The Brahmans son and the prince praised their wives and said, A home without a wife is a devils abode. They asked the Baniyas son to bring his wife as soon as he could.
The Baniyas son went to his house and said to his mother, I will go to my in-laws to bring back my wife. His mother sold, My dear son, the Venus Planet is still set. It is not visible in the sky. Wait for a couple of days. Venus is the planet of love. If you go and bring back your wife now, your married life may not be happy. The son did not agree and insisted on going to his in-laws. The parents permitted reluctantly. The young Baniya reached his in-laws house and told them about his mission. His in-laws said, The planet Venus is still setting. It will be visible after a couple of days. Parents do not send away their daughters during this period. It is inauspicious.
The boy did not agree. The parents parted with their daughter reluctantly. The couple had hardly crossed the town when the wheel of their bullock cart got damaged. The bullocks legs were also injured. The young lady was badly wounded. Still, the Youngman continued the journey despite all the adversities. As they went ahead, they encountered some dacoits. The dacoits robbed the bride of her ornaments and beat up her husband. At last, they reached home after facing many set-backs. The Youngman was also bitten by a poisonous snake and he became unconscious. The young wife wept bitterly.
The Brahmans son came to know of the incident. He went to his friends house and said to his father, Arrange return journey for them. They should not have started their journey during the forbidden period. The Venus is invisible in the sky. They will be out of danger if they go back to the in-laws. The businessman arranged their return journey. When the Youngman reached his in-laws house, he came back to himself and recovered from his illness after an ordinary treatment. He stayed there till the Venus became visible in the horizon. Afterwards, he returned to his house with his wife and lived a happy life. He started observing Friday fast regularly thereafter.