The Lion, the Witch, and the Wardrobe
How we cite our quotes:
The Witch was just turning away with a look of fierce joy on her face when she stopped and said,
"But how do I know this promise will be kept?"
"Wow!" roared Aslan half rising from his throne; and his great mouth opened wider and wider and the roar grew louder and louder, and the Witch, after staring for a moment with her lips wide apart, picked up her skirts and fairly ran for her life. (13.54-56)
Because the White Witch is herself a treacherous creature, she assumes that Aslan will try to trick her if he can. Of course, we know he would never do anything like that – and he doesn't. It's not in his nature.