成唯識論掌中樞要 2.189

2.189

燈光舒光至彼。違對法第二。破云如燈光頓發聲亦爾。勘抄。舒光者隨順理門。頓發大乘義。

That lamp light diffuses its light to reach there contradicts the second fascicle of the Abhidharma. The refutation says: "Just as lamp light is emitted instantaneously, sound is also like this." Check the notes. Diffusing light conforms to the Nyāyamukha; emitting instantaneously is the Mahāyāna doctrine.