Conversion is hardly safe. After all, it requires approaching the King of the Universe, face to face. In his book The Silver Chair, C.S. Lewis draws an analogy with the story of a young girl named Jill. She's in the land of Narnia, and she's thirsty. At once she sees a magnificent stream . . . and a fearsome lion (Aslan, who represents the Lord Jesus):

"If I run away, it'll be after me in a moment," thought Jill. "And if I go on, I shall run straight into its mouth." Anyway, she couldn't have moved if she had tried, and she couldn't take her eyes off it. How long this lasted, she could not be sure; it seemed like hours. And the thirst became so bad that she almost felt she would not mind being eaten by the Lion if only she could be sure of getting a mouthful of water first. . . .

"Are you not thirsty?" said the Lion.

"I'm dying of thirst," said Jill.

"Then drink," said the Lion.

"May I, would you mind going away while I do?" said Jill.

The Lion answered this only by a look and a very low growl. And as Jill gazed at its motionless bulk, she realized that she might as well have asked the whole mountain to move aside for her convenience. The delicious rippling noise of the stream was driving her nearly frantic.

"Will you promise not to do anything to me, if I do come?" said Jill.

"I make no promise," said the Lion.

Jill was so thirsty now that, without noticing it, she had come a step nearer. "Do you eat girls?" she said.

"I have swallowed up girls and boys, women and men, kings and emperors, cities and realms," said the Lion. It didn't say this as if it were boasting, nor as if it were sorry, nor as if it were angry. It just said it.

"I daren't come and drink," said Jill.

"Then you will die of thirst," said the Lion.

"Oh dear!" said Jill, coming another step nearer. "I suppose I must go and look for another stream then."

"There is no other stream," said the Lion. It never occurred to Jill to disbelieve the Lion, no one who had seen his stern face could do that, and her mind suddenly made itself up.

It was the worst thing she had ever had to do, but she went straight to the stream, knelt down, and began scooping up water in her hand. It was the coldest, most refreshing water she had ever tasted. You didn't need to drink much of it, for it quenched your thirst at once. Before she tasted it she had been intending to make a dash away from the Lion the moment she had finished. Now, she realized that this would be on the whole the most dangerous thing of all.