One of my favorite moments from The Lion The Witch And The Wardrobe by C.S. Lewis is the conversation between Lucy, Susan, and Mr. Beaver.
“I shall feel rather nervous about meeting a lion.”
“That you will, dearie, and no mistake,” said Mrs. Beaver; “if there’s anyone who can appear before Aslan without their knees knocking, they’re either braver than most or else just silly.”
“Then he isn’t safe?” said Lucy.
“Safe?” said Mr. Beaver; “don’t you hear what Mrs. Beaver tells you? Who said anything about safe? ‘Course he isn’t safe. But he’s good. He’s the King, I tell you.” 
What I love about this conversation is the way it captures and juxtaposes two seemingly contradictory ideas. We are forced to grapple with the fact that someone can be both dangerous and good at once — a reality not often considered. Indeed, the goodness of God should be taught, preached, and cherished; but never at the expense of his holiness. The way you and I think about God will dramatically impact the way we live. If we believe God is vindictive fear and hopelessness will characterize our lives. We will treat God like karma if we assume his actions resemble a cosmic vending machine. However, if we believe God is good, you and I will look for evidence of his goodness in our lives. Yet people often fail to realize is that because God is good one thousand times over he is also terrible. His terror is not rooted in evil. Instead, his goodness makes him terrible. Richard Sibbes said, “Outside of Christ, God is terrible.”  Do you see the point? God is infinitely good; therefore he will not tolerate sin. He is not making a moral evaluation of God. He is stating that apart from Christ, terror is the only right response when one stands before God.
Your eyes are too pure to look on evil; you cannot tolerate wrong.
Our minds struggle to grasp this kind of goodness. We are all too familiar with the destruction caused by perverted desires. We have seen the fear caused when bent men use power to bring about destruction rather than flourishing. But, our minds have no category for goodness so fierce — so intense — that it annihilates all evil in its path. How can something so destructive be simultaneously good? But this is our God. The terrible, fierce, destructive goodness of God is not a doctrine we affirm disparagingly. It is a glorious truth. Yet, you and I would be remiss to ignore that the goodness of God also confronts our sin. God’s virtue is good news only to the one who is in Christ. But for those who have not believed the goodness of God is the most terrifying news in the universe. Rather than being in close relationship with Jesus, they are in close relationship with God’s wrath.
As for you, you were dead in your transgressions and sins, in which you used to live when you followed the ways of this world and of the ruler of the kingdom of the air, the spirit who is now at work in those who are disobedient. All of us also lived among them at one time, gratifying the cravings of our flesh and following its desires and thoughts. Like the rest, we were by nature deserving of wrath.
Certainly, this is a harrowing condition to be in for, “It is a dreadful thing to fall into the hands of the living God (Hebrews 10:31).” For those who have been made alive in Jesus, the goodness of God is a source of hope and comfort. But, for those still dead in sin, the goodness of God should only cause fear. The goodness of God allows those in Christ to rejoice. Conversely, the goodness of God makes him seem terrible apart from Christ. “Since, then, we know what it is to fear the Lord, we try to persuade others (2 Corinthians 5:10).”
 Lewis, C. S. The Lion, the Witch and the Wardrobe. Collectors edition. New York: HarperCollins, 2000, pp. 79.