"This spreading of light is a frequent motif in Rgvedic hymns. The motif is worked out by the poets on two different levels, the human, and the super-human. On the human level it is the succour Indra lends to his adorants (the drya or dryavarm) in their combats against the non-vedic dasa-or dasyu tribes. On the super- human level, Indra’s (and the Aryan’s adversaries are evil-doing, demonical beings like Susna, Pipru, Vrtra, Vala, Sambara or the above-mentioned Arsasana. They also are called dasa or dasyu, their symbol is darkness, night, the depth, the lowest region of the world."