The Eyes of Our Understanding

This afternoon, Gwen and I were at lunch with a new couple from our church and I got a phone call from the school nurse where my two youngest boys attend.  A call from the nurse usually means a stomach ache or a headache to which we can easily say, "Give him some Pepto or some Tylenol and send him back to class."  Today was different.  My youngest son, Chandler (who is the most accident prone of my 5 kids) was playing soccer, tripped and ran his thumb into his eye socket.  Yikes!  We cut our lunch short and wound up in the E.R.  After a thorough examination from a wise-guy of a doctor (I won't go further down that road) it was determined that there was no cornea or retinal damage.  Whewwww! 
When I got home I started thinking about how badly his life would have been affected had there been serious damage to his eyesight.  Every area of his life would be affected dramatically. 

Paul's prayer for the Ephesian church was that

"...the eyes of your heart may be enlightened in order that you may know the hope to which he has called you..." (Eph 3:18 NIV)

Proverbs tells us that all issues of life spring up from the heart.  If our spiritual eyesight becomes damaged, it can ultimately damage our heart and greatly affect all of the issues of our lives.  We need to guard against that and pray the same prayer over our lives that Paul prayed for the 1st century Ephesians. 

What are some things that can damage our spiritual eyesight and what can we do to make sure that the eyes of our understanding stay enlightened?