It feels like night vision is required when looking into our own life or the life of another. We can make out the shape of some things that seem to be significant in the discovery of who we are, but they remain fairly dim and undefined or can disappear altogether.
I remember several late evenings (actually early mornings) getting up and walking into the kitchen to get a pain reliever for a headache. I would leave the lights off hoping not to wake my wife and avoiding any other reasons for my head to hurt.
As I would walk through the dark living room, I would sometimes catch a glimpse of a pair of shoes or the vacuum cleaner with my peripheral vision. As I tried to focus directly on it, it would often disappear. As soon as I looked straight ahead, I would see it once again. Why?
In the same way, have you ever noticed an airplane or a satellite moving across the dark evening sky and as you attempt to follow it, it disappears? Why?
I found the answer in a firearms training course I recently took, as the instructor talked about dim light shooting and eye sight. I discovered a transcendent truth in a most unlikely place.
The iris is like the shutter of a camera, opening and closing to regulate the amount of light entering the eye though the pupil. When we talk about eye color, we are talking about the iris.
The retina is similar to the film in a camera. The retina is struck by light coming in through the pupil, forming an image, and then causing an impression to be transmitted to the brain through the optic nerve.
The retina is composed of two different types of cells -‐ cone cells and rod cells. The cone cells are your “day eyes” because they require a great deal of light to activate them and they are blind during periods of low-‐illumination. These cells enable you to see color, shape, and contrast.
Your “night eyes” are your rod cells. They produce a chemical substance called visual purple, which makes them active in darkness or periods of low-‐illumination. They enable you to distinguish black, white, and shades of gray, and to distinguish general outlines.
Alright, here is where I’m going with all of this – the principles of night vision.
First, we must give our eyes time to adapt to low levels of illumination. It takes approximately 20-‐30 minutes for the rod cells to produce enough visual purple to activate and enable you to distinguish objects in dim light.
Too often we want instant clarity and when it doesn’t come, we stop looking – we walk away from our search. Clarity always come in degrees and over time. It takes time for the eyes of our heart (Eph. 1:18-‐ 19) to adjust to the often dim light over our story. “People’s thoughts can be like a deep well, but someone with understanding can find the wisdom there.” (Prov. 20:5 NCV) Deep wells are always dark.
Secondly; in dim light, we must keep our attention on an object without looking directly at it. Looking directly at an object focuses the image on the cone region which isn’t sensitive at night. To form the image on the rod cells we need to look slightly to the right, left, below or above an object. The visual purple in the rod cells blacks out in four to ten seconds and you lose sight of the object, so we must move our eyes swiftly so fresh rod cells are used. We must pause for a moment at each point because our eyes can’t see while in motion.
The human heart and the work of God is vast, complex and mysterious. When we focus on one aspect of our heart or life for a long period of time to the exclusion of others, it often becomes imperceptible. Looking around an issue, question or desire often allows it to come into focus. We must continue to scan the landscape of our life and God’s heart.
Thirdly, confidence plays a very important role in our use of night vision. Normally we use our eyes when there is plenty of light and we see sharp outlines and bright colors. When we are in darkness, objects are faint, have no sharp outlines and have little or no color. We must believe what our eyes tell us. We gain confidence by practicing these principles of night vision.
As we are willing to delve into the dimly lit recesses of a person’s story and glory, offering what we see, we will become more comfortable and skilled with our night vision.
“Now we see a dim reflection… All that I know now is partial and incomplete…” (1 Cor. 13:12)
Learning to see better,