In Hinduism, Thursday is dedicated to Lord Vishnu and Lord Brihaspati, the Guru of all Devas. Thursday is also called Brihaspativaar or Virhaspativaar. The people who observe the Brihaspati fast and sincerely perform the puja are blessed with wealth and good health. However, some devotees perform the Brihaspati Puja Udyappan, which is of considerable significance, according to Hindu mythology. Brihaspati Puja Udyappan is regarded as a celebration of thanksgiving and gratitude towards the Lord. It is also a way to show appreciation to the god for allowing the devotee to perform the Birhaspati puja and observe the vrat for the required number of days. The Brihaspati Vrat Udyappan is a concluding ceremony after completing Brihaspati fast as
Advised by the Pandit or the priest for seven days, nine days, 16 days, 45 days, 52 days, 108 days, etc. After completing the vrat for a specific number of days, one performs Udyappan. One can observe the vrat for a minimum of 7 Thursdays and a maximum of 108 Thursdays. If a devotee is keeping Sanma vrat, then it requires a fast on Thursday for a lifetime on the day of Udyappan, the devotee gets up early in the morning, takes a bath, and clad him or herself in yellow-colored clothes. After this, one can begin with the rituals of Brihaspati Puja. One must perform the puja without consuming any solid food. After completing the puja rituals, one can have milk and fruits. It is essential to chant the Lord Brihaspati mantra throughout the day of Udyappan. On the day of Brihaspati Udyappan, after completing the puja rituals, one must distribute curd rice among the poor and needy people. Minimum 9 people should be given curd rice. If a person is rich, he or she can donate money, clothes like a dhoti, saree, etc. After giving the alms, one must have the curd rice to complete the vrat. On completing the day of Brihaspati vrat, one is done with the Udyappan of the Thursday fast.