The quote from the sermon:
“But faith–unlike the other kind of knowledge–is not a constant. It is a light which blazes like a thousand suns–at some times; at others, it flickers dimly, casting shadows of changing shapes. But even when it is weak we struggle to brighten the flame–for it is the most precious of commodities. Man knows no blackness to match the darkness when that light has gone out. And no man who has ever seen it will rest happy until it is rekindled. And when it burns bright, all other lamps are feeble.” –Rabbi Chanan Brichto, as quoted by Dr. John Walton