Devibhagavatapurana 5.2.3

5.2.3

vyāsa uvāca |
śṛṇu rājan pravakṣyāmi vistareṇa mahāmate |
śraddadhānāya śāntāya na brūyātsa tu mandadhīḥ ||

Vyâsa spoke:-- O king! You are very intelligent; I will describe in detail all this to you; whoever does not describe Her Glory to the peaceful and faithful, is certainly low-minded? In days of yore, a terrible battle ensued between the Devas and Dânava forces on this earth when Mahisâsura was the Ruler of this world. O king! Mahisâsura went to the mountain of Sumeru and performed a very severe and excellent tapasyâ, wonderful even to the gods. O king! Meditating on his Ista Devatâ (the deity for his worship) in his heart, elapsed full ten thousand years, when Brahmâ the Grandfather of all the Lokas, was pleased with him. The fourfaced Brahmâ, arrived there on his vehicle the swan, asked Mahisâsura “O One of virtuous soul! Ask from me what is your desired object; I will grant thee boon.”