Like the gift of water, Yama, from desire of doing good to the departed manes, applauds the gift of lamps to light dark places, for it is considered as benefiting the departed manes.
तथा प्रशंसते दीपान् यमः पितृहितेप्सया। तस्माद् दीपप्रदो नित्यं संतारयति वै पितॄन्।॥