The Ekadasi that falls during the Krishna paksha (waning phase of the moon) of the Shravana month of the is known as Kamika Ekadasi. The glories of Kamika Ekadasi are described by Lord Brahma to sage Narada and also by Lord Krishna to king Yudhishtira. The details of this glorious Kamika Ekadasi are found in Brahma .
It is considered that on the Ekadasi that occurs during the Shukla paksha (waxing phase of the moon) of the Ashada month, Lord Vishnu along with all the other gods goes to sleep. Thus, this Ekadasi derives its name, “Devshayani”, wherein, “Deva” stands for God and “Sayana” refers to sleep. The glories of Devshayani Ekadasi are mentioned in the Bhavishya-uttara Purana as explained by to king Yudhishtira. Earlier, the glories of Devshayani Ekadasi were narrated by Lord Brahma to Narada Muni.