The Sarvadurgatipariśodhana tantra (SDP) has informed Tibetan Buddhist funerary practices since it was first translated into Tibetan in the late eighth century. One of its most influential interpreters was the Sa skya pa hierarch Rje btsun Grags pa rgyal mtshan (1147– 1216), whose Light Rays for the Benefit of Others: The Rituals of Sarvavid offers detailed instructions for performing the SDP’s rites. Light Rays became a source of contention for some later scholars, most notably the prolific Bo dong Paṇ chen Phyogs las rnam rgyal (1375/6– 1451) and the Sa skya pa luminary Go rams pa Bsod nams seng ge (1429–89). Bo dong Paṇ chen’s Definitive Explanation of the Rituals of Sarvavid Vairocana is highly critical of Light Rays, while Go rams pa’s Overcoming Harm for the Benefit of Others defends Light Rays against Bo dong Paṇ chen’s critiques. This article considers the context of this dispute before examining three of the topics discussed: the necessity of purifying the site of the ritual, visualization practices associated with the object representing the deceased, and the relationship between the SDP’s framing narratives and the rituals that free the dead from bad rebirths. It also reflects on the relevance of these two works for understanding ritual polemics as a form of Tibetan polemical writing.