Have you had your eyes examined lately? The last time my eyes were examined, I felt tense having that puff of air come toward my eye to test for glaucoma. I knew it was coming and the longer I waited for it, the more tense I became. I knew it wouldn’t hurt me, but it still scared me. I wanted to push the machine away and protect my eye. 
Do you feel like your eye is one of the most sensitive parts of your body that you want to protect? I do. It just feels so scary and dangerous to have anyone pointing something close to my eyes. There’s an automatic reflex that says, “Get away! I will protect my eyes!”
 
Do you know that God feels the same way about you? He will protect you just like you and I want to protect our eyes. How do I know? That truth is found in Zechariah 2:8. You’ve heard the verse before: “for whoever touches you touches the apple of his eye—” (NIV). But maybe you’re like me. I didn’t really understand what it meant.
In this verse, the word “apple” refers to the pupil which is the opening of the eye allowing rays to reach the retina. It is the tenderest, most vulnerable part of the eye. The slightest injury can bring huge problems, the worst being blindness. No wonder God has designed us to instinctively protect our eye. He knows the consequences are serious.
 
The NLT words it this way: “For he said, ‘Anyone who harms you harms my most precious possession.'”
Clarke’s Commentary offers this fascinating insight:

This is a remarkable expression. Any person, by looking into the eye of another, will see his own image perfectly expressed, though in extreme miniature, in the pupil. Does our English word babbet or baby come from this? And does not the expression mean that the eye of God is ever on his follower, and that his person is ever impressed on the eye, the notice, attention, providence, and mercy of God?

Just as God knows and created the vulnerability of the pupil, He knows the weakness of His earthly human creation. Psalm 103:13-14 assures us: “Just as a father has compassion on his children, So the Lordhas compassion on those who fear Him. For He Himself knows our frame; He is mindful that we are but dust.” Therefore, He is motivated to protect.
 
Yet, our question is, if He’s protecting us, why do bad things happen? God’s motivation is not for us to be injured but He does allow bad things to happen so that we will need Him. His motivation is that we will be purified in preparation for heaven. 
The puff of air from the glaucoma testing machine comes toward us and seems dangerous. Likewise, we can actually look at trials and problems coming toward us as potentially dangerous but they don’t have to hurt us if keep our trust in God. And because God wants to protect us, we can turn to Him for His help. 
I know we don’t feel protected or like the apple of God’s eye when we are tested, tried, and tempted. But remembering how God regards us will help us. We are precious to Him, as precious as your pupil is to you for your sight. Remember that every time you block some potential danger from reaching your eye.