Allah is the light of the heavens and the earth; The similitude of His light is as a niche in which is a lamp, and the lamp is in a glass, the glass is as though it were a brilliant star; it is lit from a blessed tree, an olive neither of the east nor of the west, the oil of which would well-nigh glow of itself though no fire touched it; light upon light! Allah guides whom He will to His Light; and Allah strikes out parables for men, and Allah knows all things.