The concept of Vishnu obtaining the three worlds for the Devas from the Asuras in three steps is clearly explained in the Aitareya Brahmana. The RigVeda Samhita verse referred to (6.69.8) regarding Indra and Vishnu battling the Asuras states 'Ye Twain have conquered, ne'er have ye been conquered: never hath either of the Twain been vanquished. Ye, Indra-Viṣṇu, when ye fought the battle, produced this infinite with three divisions'.