The essence of any being is the underlying substance that is the basis for its existence.
The essence of a human is complex with three different parts; body, soul, and spirit (1 Thessalonians 5:23). Each part is necessary for existence: the spirit is our rational part, the soul is our emotional center, and the body is how we express ourselves. In contrast, God’s essence is simply spirit. Out from this essence God is.
God’s Essence is Spirit
God is spirit, and it is necessary for the ones worshiping Him to worship in spirit and in truth, John 4:24.
Spirit is a real, immaterial substance which is the basis of God’s being.
God is not a man, so although we use images and descriptions of men to describe God, such as the hand of God, we need to be careful not put Him into the box of humanity that limits Him to what we are. He is a completely different being than mankind. Although Adam (the first man) was created in His likeness and image this does not make man in any way equal with the type of being God is. Likeness means that man is intelligent in a similar way to God and image refers to Adam’s outward appearance being covered with a garment of light. As offspring of Adam we inherent his likeness and image. Unfortunately, this is after his fall, in which the garment of light was stripped and his nature corrupted (Genesis 5:3; 3:10 – they were stripped).
God is not a man that He should lie, nor a son of man that He should repent…, Number 23:19
God has life within Himself.
For just as the Father has life in Himself, thus also the Son has life in Himself, John 5:26.
This is not an attribute, which describe what the essence can naturally do. This is a description of the essence itself. God does not need anything to exist because His substance has within itself the ability to sustain it own life.
Using simplicity to describe the essence of God is to simply state that He will always be spirit and nothing else. In 1 Timothy 1:17 we are told that God is incorruptible. His essence never changes or diminishes.
In Ephesians 4:10 and Hebrews 4:14 Christ ascends above the third heaven into an area that is beyond the universe. For Christ to do this it would mean that His essence is beyond or greater than the universe and therefore immense.
Being immense, God is omnipresent. Omnipresent is not describing an attribute, but the essence because an attribute must be true at all times, where omnipresent is only necessary when creation is present.
There is only one God, yet, He has three persons. The persons are individual and distinct from each other; however, they all share the same essence. This makes them the same being. not three beings.
I and the Father are One thing, John 10:30.
Christ is not saying He is the Father; rather, He is stating that they both are the same essence. God made it very clear to Israel in Deuteronomy 6:4 that He is One God. Even the demons know this – You believe that God is one. You do well. Also the demons believe and shudder, James 2:19