My favorite illustration ever about this idea — this reality — that God isn’t safe, comes from C. S. Lewis.
Speaking of Aslan, Lucy asked,
“Then he isn’t safe?”
“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.”
C. S. Lewis, The Lion, the Witch, and the Wardrobe, Macmillan, 1950, p. 75-76