Quote from
http://www.dharmaprotector.org/nyingma-gelug.htmlSome people believe that if Gelugpa practitioners practice Nyingma teachings, Dorje Shugden will harm them, but this is completely wrong. We never believe this. Impossible. Besides Dorje Shugden, there are many Tibetan stories of other Dharmapalas killing people. There is even a lama called Ra Lotsawa who killed thirteen tantric masters including Tarma Dode, Marpa’s son. This is not just superstition. Many monasteries, maybe including Namgyal Dratsang (His Holiness the Dalai Lama’s private monastery), engage in the practice of Yamantaka that comes from Ra Lotsawa’s instructions. So shouldn’t they stop this practice because Lama Ra Lotsawa was a murderer? This would be meaningless. It is similar with Dorje Shugden, but there is no evidence of Dorje Shugden harming anyone. It is just superstition. For example, if a Gelugpa lama who practices Nyingma teachings has an accident, then some people think, “Oh, this is Dorje Shugden’s fault.” This is stupid. Then they write a book about these things, but this is not real evidence.
(
Geshe Kelsang Gyatso, An Interview With Geshe Kelsang Gyatso, Tricycle: the Buddhist Review, No. 27, Spring 1998, p. 76)