***DISCLAIMER*** The following is far from an exhaustive answer to the question. It is simply an answer nonetheless.
Recently, someone asked me how he/she should respond to unbelievers who believe God is simply energy who only gives light. Below is the question followed by my response to it.
How do I respond to unbelievers who claim God is simply energy who only gives light?
It is important to understand that unbelievers are incapable of understanding the things of God since the things of God are foolishness to unbelievers (1 Corinthians 2:14). It is commonplace for unbelievers to have perverted views of God. This includes but is not limited to the view that God is simply energy that only gives light. Nowhere in Scripture is the word “energy” even found. As a result, to state that God is simply energy that only gives light is unfounded. It is basically manmade doctrine.
The Scriptures have much to say about God. In short, one must consider God’s work, nature, character and relationship with mankind. The Scriptures state that God is just (Acts 17:31; Exodus 34:7), loving (Ephesians 2:4-5; 1 John 4:8), truthful (John 14:6; Malachi 3:6; Titus 1:2; Numbers 23:19); holy (1 John 1:5), compassionate (2 Corinthians 1:3), merciful (Romans 5:8, 9:15) and gracious (Romans 5:17). He is also the world’s creator and sustainer (Genesis 1:1; Isaiah 42:5; Colossians 1:17). The Scriptures themselves are inspired of God and thus unbreakable, true and profitable for many a great thing (2 Timothy 3:16-17; 2 Peter 1:16-21; John 10:35; Psalm 12:6). Most importantly, God sent His Son, Jesus Christ (the infinite God-man and the only way by which mankind may be saved) to die for the sins of the world (John 1:1, 14; Isaiah 53:6; Matthew 1:21; John 1:29; Acts 4:12; John 14:6; 1 Timothy 1:15). Every single one of us has sinned and broken God’s holy law (Romans 3:23). One simply needs to look at the Ten Commandments to see how he/she is guilty before a holy God (Exodus 20:1-17). Thankfully, by repenting and trusting in Jesus Christ alone by faith for salvation (Acts 16:31; Romans 10:17; Galatians 3:2; Romans 6:23; 2 Timothy 2:24-26; Ephesians 2:8-10; Matthew 3:8; Titus 3:8; Acts 2:38; Mark 1:15; 2 Peter 3:9), one can free his/her self from sin, death and the devil.
I hope this is a good start in your witnessing to unbelievers who think that God is simply energy that only gives light.