This verse was cited by the Muslim caller as another example of Qur'anic parable language, and the response challenged whether its imagery was explained clearly enough to prove divine origin.
Scripture spotlight
Quran 24:35
quran
35 God is the Light of the heavens and the earth; the likeness of His Light is as a niche wherein is a lamp (the lamp in a glass, the glass as it were a glittering star) kindled from a Blessed Tree, an olive that is neither of the East nor of the West whose oil wellnigh would shine, even if no fire touched it; Light upon Light; (God guides to His Light whom He will.) (And God strikes similitudes for men, and God has knowledge of everything.)
Cited from a Muslim perspective to argue that Allah being light makes darkness a metaphor for sinful deeds and countenance, not a literal change in skin color.
Cited to support the Muslim-side argument that Allah’s light represents goodness, so language about darkened faces refers to spiritual countenance rather than physical skin color.