Pradosh vrat is one of the auspicious fasts dedicated to Lord Shiva and Maa Parvati. It is also known as Pradosham and marks a major sacred observation by the devotees of Lord Shiva. Pradosh vrat is observed during the Pradosh period (Sandhya Kala) on Trayodashi tithi (13th day) of both lunar fortnights. The auspicious Pradosh period is 3 hour period (1.5 hours before and after the sunset); which is one of the optimum times for the worship of Shiva.The Puranas have mentioned this very interesting Katha of Pradosh Vrat which is associated with the Samudra Manthan advised by Lord Vishnu. The very famous Amrit – which had the capacity to make anybody live forever was extracted from the sea by churning it. The Devtas and Asuras were involved in the churning which produced the Amrit along with a very powerful poison that had the capacity to destroy the entire universe.

This poison had to be destroyed but nobody got a solution for the same. In the end, Lord Shiva came to rescue and he drank the poison Halahala. This made him shout with pain in his throat. To cool down the effect of the poison, Goddess Parvati placed her hands on the throat of Lord Shiva and released him from the suffering. The Devas and Asuras thanked Lord Shiva on Trayodashi tithi. Pleased with the devotion, Lord Shiva is believed to have danced between the horns of Nandi – the bull. The time when Shiva was extremely happy was the Pradosham period or the twilight time of the Trayodashi tithi. Since then that day, Pradosh vrat is observed on Trayodashi tithi by devotees to get the blessing of Lord Shiva.