Skanda Purana — Prabhasa Khanda, Shloka 41
दीपं प्रज्वालयेद्रात्रौ यः स्तवैर्हरिजागरे । न चास्तं गच्छते तस्य पुण्यं कल्पशतैरपि
dīpaṃ prajvālayedrātrau yaḥ stavairharijāgare | na cāstaṃ gacchate tasya puṇyaṃ kalpaśatairapi
夜に、讃歌をもってハリの夜の覚醒（ジャーガラ）を守りつつ灯明をともす者—その功徳は、幾百のカルパを経ても減ずることがない。
Brahmā (deduced from discourse continuity)
Tirtha: Dvārakā
Type: kshetra
Scene: A devotee in Dvārakā at night lights a steady lamp before Hari’s image, while groups chant stotras; the lamp’s glow symbolizes merit that does not wane across kalpas.
FAQs
Even a simple offering like lighting a lamp, when joined to vigilant devotion and hymn-singing, becomes imperishable merit.
Dvārakā, where Hari’s night-vigil and lamp-offering are acclaimed as extraordinarily meritorious.
Lighting a lamp at night during Hari-jāgaraṇa while reciting stotras (hymns).