But as for you and your servants, I know that you do not yet fear the LORD God.
Pharaoh and his servants have experienced a bit. They have seen the initial miracles — water into blood, staves into snakes, frogs coming out of the river, little flying insects everywhere — as well as some of the early plagues like hail killing off all of their livestock and a severe hailstorm wiping out crops and even killing people. Despite all of this, Moses tells Pharaoh that he and his servants do not yet fear the LORD God.
Pharaoh demonstrates this with his actions. He promises to let the Israelites go, then goes back on his word and does not let them go. And the fact that no one around him is making a case for letting the Israelites go is the evidence that they, too, do not yet fear the LORD God.
What of my own life? Do my actions display a fear of the LORD God? Do I behave as one who knows that God can and will judge? Do I behave as one who knows that God chastens those who are His? It is, as Pharaoh and his entourage illustrate, entirely possible to see the power of God and recognize it as such and not modify my behavior in a way that shows I have internalized the truth.
Father, thank You for the reminder that truth, no matter how recognized and assented to mentally, must change my behavior before it becomes a matter of belief. Please work in my life to change me; to make my life one that reflects a healthy and right fear of You.