I am grateful to every optician who ever ground a lens.  I have worn glasses for half a century, since my third-grade teacher discovered I couldn't read the blackboard.  Every driver's license has read, "Corrective lenses required."
   Sometimes I wonder, "Corrected to what standard?"  Any lens brings certain things into focus, while distorting others.
   I began thinking about this last year.  Tired of tipping my head back to read the computer screen through the lower portion of my progressive bifocals, I got glasses just for computer work. What a relief! The lenses are ground to provide clear vision at just the distance from the computer screen.  My eyes are far less tired at the end of a day's work.
   Of course, everything not at the distance of the computer screen is out of focus.  To read while wearing those glasses, I have to hold the book or magazine at arms' length.  Looking across a large room, I can still see where everything is, but I cannot recognize faces. 
   Corrected to what standard? 
   Wearing computer glasses reminds me of a story:  A rabbi and his students were discussing Sabbath, which begins at nightfall on Friday.  The rabbi asked, "Now, how do you tell when night has fallen?  Suppose it's cloudy; you cannot see the sun set.  How do you tell when night has fallen?" 
   One student suggested that if you look at a flock of sheep, night has fallen when you can no longer see the white sheep in the darkness.  Another student said, "What if there are no sheep nearby?  To tell when night has fallen, I say you hold two threads in your hand, one red and one blue.  When you can no longer tell them apart, that is when night has fallen."
   "Two good answers," said the rabbi.  "Let me suggest another.  Whenever you look into the face of any man and you do not recognize him as your brother, whenever you look into the face of any woman and you do not recognize her as your sister - that is when the darkness has truly come." 
  With my computer glasses on, I cannot recognize people at a distance.  What "corrective lenses" do you wear that prevent you from recognizing any man as your brother, any woman as your sister, any human being as a child of God?
 
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