Why “light” is a symbol for God in the Bible-explained scientifically

The bible refers to God as “light”:

“This is the message which we have heard from Him and declare to you, that God is light and in Him is no darkness at all.”
[1 John 1:5, Bible, NKJV]

This short scientific discussion of Einstein’s E=Mc2 equation powerfully explains why one of the metaphors for God in the Bible is “light”.  

She says that:

1. Light or photons have no mass, and that they are pure energy. 
2. For anything traveling at the speed of light, both space and time compress to a single point. 

In other words, if God is “light”, then he transcends both space and time and is pure energy.