2 Corinthians 4:18 (NKJV)
If you have ever been outside in the dark, where there was not much light, you know that it can be difficult to see things. Eventually, your eyes will adjust to the reduced amount of light and then you can see things better. This does not happen instantaneously, but it is amazing how much we can see in the dark once our vision is adjusted. There are also different devices available that can help us see in the dark, but just with our eyes adjusting to the lower light level, we can have a better view of things in the dark than we did at first.
Normally, and especially before we are Christians, we view things from a natural perspective, but as Christians, we need to have our "eyesight" adjusted to see things from a spiritual perspective. If we do not get our "eyesight" and perspective adjusted to seeing things from the spiritual, and not the natural perspective, we will not only miss out on things that God is trying to reveal to us in His Word by the Holy Spirit, but we will live a life based on natural facts and not spiritual truth, and we will live below the standard that God has for us.
The Bible says we live by faith and not by sight (2 Corinthians 5:7) and that we do not look at, we do not focus on what is seen, natural circumstances, but what is unseen, spiritual truth (2 Corinthians 4:18). When we look at things from a biblical perspective, at first it might be hard to do, but eventually it becomes easier for us as we adjust to seeing things based on biblical truth. Just like having our eyesight adjust to different light levels, we need to adjust our perspective on how we view things, to go more from the natural to the spiritual.