vishwamitra samhita

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Sun

After glorification of pilgrim spots, the glory of Gayatri, rise of Vishwamitra from the position of Rajarshi to Brahmarshi with the blessing of Goddess Gayatri, and the main names of Lord Sun (Suryadev) and his mantra have been described. In this context, it is said that Lord Sun remains present in all the ten directions. He is worshipped with Gayatri mantra. The men who bow to Suryadev, become as radiant as him. The men who perform yajna after taking bath at the dawn on the day of Sunday in the month of Paush become free from lust, anger, and attachment. Those who perform shraadh (post- funeral rite) related with forefathers and feast Brahmins on this day secure the supreme position. Those who make worship of Sun during the period of Sankranti never face adversity.

Source
http://knowledgefruit.blogspot.com/search/label/SkandaPurana