Visible light can be defined as the electromagnetic radiation within the portion of the electromagnetic spectrum that can be perceived by the human eye. It has wavelengths in the range of 400-700 nanometers. It’s primary properties are intensity, propagation direction, frequency or wavelength spectrum, and polarization. It’s speed in a vacuum is 670,616,629.3844 miles per hour. That is about 3,000 times faster than a bolt of lightning.
In one of the seven “I Am” statements made by Jesus, He said, “I am the light of the world.” (John 8:12) As the Creator He is the source of all light. He not only is the source of visible light but He is the source of spiritual light. Just as physical light is essential to the existence of physical life, so spiritual light is necessary for spiritual life. To be without spiritual light is to be without spiritual life. To be in spiritual darkness is to be unable to know Him.
Physical light must be present to see things physically. In like manner, spiritual light is necessary in order to see spiritual truth. He is the light giver. In this life, our spiritual vision is limited. Paul said, “For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.” (1 Cor 13:12) But John tells us in Revelation 22:5 that in heaven our limitations will be removed because we will be forever with the source of light.
by Dr. Gayle woods