The Holy Quran Makes Things Clear

AN-NOOR (THE LIGHT) : 34-35

24:34. We have already sent down to you verses making things clear, an illustration from (the story of) people who passed away before you, and an admonition for those who fear (Allah).
24:35. Allah is the Light of the heavens and the earth. The Parable of His Light is as if there were a Niche and within it a Lamp: the Lamp enclosed in Glass: the glass as it were a brilliant star: Lit from a blessed Tree, an Olive, neither of the east nor of the west, whose oil is well-nigh luminous, though fire scarce touched it: Light upon Light! Allah doth guide whom He will to His Light: Allah doth set forth Parables for men: and Allah doth know all things.