In Surah Maedah, Verse no. 15 Allah says that A light (noor) and obvious book has come to you from Allah.
Ali ibn Ibrahim Qummi narrates that the light is Holy Prophet PBUH, Amirul momneen and Aimma.
Tafseer-e-Qummi, Vol. 1, P. 172
Also see: Tafseer e Qurtabi, Vol. 6. p. 117. In this Tafseer, one of the interpretations of the noor is given as Muhammad PBUH.
Note: This commentary on Quran is written by one of the famous Ahlu sunnat scholars and commentators.
You should ask your class fellow that what does the noor mean in this verse except our Holy Prophet PBUH?