God is eternal. In fact, He is the only being or thing that is truly eternal. Even heaven, hell, angels, demons, and the human soul can only be considered eternal in a futuristic context. All of these things, though they have no end, did have a beginning. Only God is without beginning and without end.
Only God is wholly unrestricted by the reality of time. Since God is unrestricted by time - He is the very force that restricts time itself - from His vantage point all things are present. Though He chooses to reveal Himself to us within the framework of time it must be understood that He does so to accommodate our inability to grasp anything outside time and space, not because He Himself is confined by it.
This is a lofty concept. But is it useful? What use is it to know that God is eternal? Here are two quick thoughts.
God Does Not Need You
"During eternity past, God was alone: self-contained, self-sufficient, self-satisfied; in need of nothing...had God so pleased He might have continued alone for all eternity, without making known His glory unto creatures. Whether He should do so or not was determined solely by His own will. He was perfectly blessed in Himself before the first creature was called into being."
(A.W. Pink)
We associate being alone with the negative experience of loneliness. We do not experience that feeling because we are alone. We experience that feeling because are in need of something that we are inadequate to provide within ourselves.
Why? Because we are created. Therefore, our entire existence and meaning is found in the Creator. We need that which is outside ourselves. So when we are alone, left with our own thoughts and inner workings, we experience the lack of the fulfillment of that need. And we call this experience loneliness.
God is not like this. He has, from all eternity, everything needed, everything desired, everything valuable, enjoyable, and pleasurable; all within Himself. He is the only being who can boast perfect self-satisfaction. He is the only being who can be alone without loneliness. Our company does not make God more satisfied.
This is useful because it keeps us in our place. Human nature desires to be placed in positions of great importance. If God needs us, that means He is lacking something without us. If this is true we can make ourselves out to be much larger and God much smaller.
We need the humility that comes from this realization. Our entire Christian lives consist of grace from God to undeserving sinners for His glory.
You can add nothing to God, but He is everything you need.
Understanding God's Eternality Gives Us Greater Assurance
Philippians 1:6 says, "And I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ." I have a new appreciation for this verse because of the eternal nature of God. Hear this and see if it does not warm your soul.
If you are in Christ, right now God is dwelling with you in the new heaven and new earth. Let me explain. Since you are confined by time you can only understand things in terms of time and space. So right now you are reading this post. In the past you were converted. In the future you will enter into God's eternal presence.
This is where we so often get hung up. When hard things happen and it seems like we are being destroyed, we begin thinking, "God, I thought you were a good God! I thought you were working all things for good! This is not good!" We react this way because we can only see and feel the particular moment we find ourselves in. But God may well say to us,
"You are not seeing what I am seeing. At one and the same time, I am watching your birth, your conversion, every moment of suffering in this life, every moment of joy in this life, and the one millionth year of your eternal joy in heaven."
You see, God sees every moment of your existence - past, present, and future - all at the same time as if they are all happening at the same time. So you may be basing your feelings and reactions on what you see happening within the confines of time, but God sees it all at once. So when God inspired the words of Philippians 1:6, the certainty from God's angle is not "I am going to complete you", but, "I already have."
No matter what hardship you see in this moment of your life you can remind yourself of this:
Right now God sees me going through this thing, but right now He also sees me dancing in the streets of Heaven as if my suffering never occurred.
What assurance!