Read Psalm 17.
I was born cross-eyed with a severe astigmatism, and I underwent eye surgery when I was just nine months old. But the operation only repaired so much, so I wore pretty thick glasses until just a few years ago. I also had to wear a patch over my left eye for seven years.
Growing up, I went to the eye doctor all the time for checkups. I knew my eyes were bad when the doctor would call in other doctors and say, “Hey! Take a look at this!” But my least favorite part of these visits was getting eye drops. The doctor would have me lie down. Then he’d hold open my eyes, one at a time, with his gloved finger. He’d hold a plastic bottle of solution over the center of my eye and try to get me to sit perfectly still so he could squeeze the bottle and drop a numbing agent into my pupil.
The point of dilating a person’s eyes is so that their eye muscles relax. Apparently, there’s some cool stuff that can only be seen when the pupil is open against its will. But in this horrible ritual every other muscle in my body tightens. There’s just something about looking up—because you can’t close your eyes when the doctor’s hand is forcing your eyelids open—and seeing something pointed directly at the center of your eye. It’s unsettling to say the least. Every instinct and impulse tells you to protect your eyes. Nothing is supposed to touch them.
In Psalm 17, David prays, “Keep me as the apple of your eye” (v. 8). I used to think being the apple of someone’s eye meant you were like a delicious apple that the person had their eye on. But the “apple” language comes from early English translations of the Bible. What’s meant here is the “pupil” or “center” of the eye. David is asking God to protect Him the way a person protects their eyes.
God is spirit (John 4:24), so He doesn’t have physical eyes to protect. And since He’s God, He has no vulnerability whatsoever, actually. He has nothing in need of protection. There’s no Achilles’ heel where God is concerned. But David knows that in the past God has protected His people as a man protects the center of His eye. He’s actually borrowing from the book of Deuteronomy: “He shielded him and cared for him; he guarded him as the apple of his eye” (32:10). (The “him” in that verse refers to “Jacob” [see v. 9], i. e. the nation of Israel, since the twelve tribes all descend from Jacob.) Though God is invincible, impenetrable, and invulnerable, His people are not—and He protects them with the same ferocity with which a person protects his own eyes.
There’s another image David uses in Psalm 17. He prays, “Hide me in the shadow of your wings” (v. 8). Once again, David is borrowing from Moses’ song in Deuteronomy 32, the verse following the “apple of his eye” bit: “Like an eagle that stirs up its nest and hovers over its young, that spreads its wings to catch them and carries them aloft” (v. 11).
God cares for His people the way a mother bird protects her young. This metaphor will be used again and again in Scripture (see Ruth 2:12; Psalm 36:7; 57:1), culminating with Jesus’ famous words: “Jerusalem, Jerusalem, you who kill the prophets and stone those sent to you, how often I have longed to gather your children together, as a hen gathers her chicks under her wings, and you were not willing” (Matthew 23:37).
In Christ, you and I are the apple of God’s eye. We are hidden in the shadow of His wings. At times, it may seem that we are on our own, vulnerable and unguarded, but that’s just the way it seems. God does not let anyone poke Him in the eye.