God is not a temporal being. Namely he is not in the realm of time. Humans are. This temporality means that we can grow, develop, and mature. Another way of saying this, is to say that we have potential. With external circumstance and internal motivation, we activate our potential.
To say that we have potential is to say that we are in the process of becoming. We might liken this to the potential that Ussain Bolt had when he was growing up as a child. With the right diet, training, and opportunity, he would be able to reach his full potential as a sprinter. Ussain Bolt needed external circumstances to help him become the greatest sprinter in the world. Ussain Bolt needed these things to reach his potential. God is unlike Ussain Bolt. He does not need anything to reach his potential. He is always fulfilling all of himself.
It is improper to say that God has any potential. Why? Because, it would mean that portions of God’s “self” need something (besides himself) to make him either “more God” or “better God.” This is incorrect because God is a self-existing being who is always God. As God he is already perfect. To self-exist means to have everything needed to exist and be a one’s total self (always). If we say that God is temporal and thus has potential, we are then also saying that God does not hold the entirety of his life (always). On the contrary, God cannot be made better. He never grows.
As humans, the stretch of our life is held in sequence. We don’t have the entirety of our life always before us. We have years to experience our life. God’s experience is not a linear pathway like our own. Let’s go back to sprinting to illustrate. As Ussain Bolt runs the 100-meter dash he goes from the start to the finish. Linear. God, however, is not in time. His experience of everything is always. Of course, something like this is difficult to understand at first glance. One helpful way for some is to like God’s perspective to a dot in the middle of a circle. As humans we are at any given point around the circle (depending on what time period we live in). God is like the dot in the middle of the circle. From His perspective he can see every point on the circle always (see picture).
The implications of God being eternal mean that God has total knowledge of everything that happens in our future. Like the dot he sees everything always.