Gleanings — Paragraph 197

He, verily, is the Compassionate, the All-Merciful. Say: So great is the glory of the Cause of God that even the blind can perceive it, how much more they whose sight is sharp, whose vision is pure. The blind, though unable to perceive the light of the sun, are, nevertheless, capable of experiencing its continual heat. The blind in heart, however, among the people of the Bayán — and to this God is My witness — are impotent, no matter how long the Sun may shine upon them, either to perceive the radiance of its glory, or to appreciate the warmth of its rays.