C.S. Lewis quote-of-the-week

One of my favorite and commonly-used analogies...to deal with the error that Christians will necessarily behave better than non-Christians.

“If Christianity is true, why are not all Christians obviously nicer than all non-Christians?...If conversion to Christianity makes no improvement in a man’s outward actions…then I think we must suspect that his ‘conversion’ was largely imaginary…But there is another way of demanding results [which] may be illogical…If Christianity is true then it ought to follow (a) that any Christian will be nicer than the same person would be if he were not a Christian; and (b) that any man who becomes a Christian will be nicer than he was before. In the same way, if the advertisements of Whitesmile’s toothpaste are true, it ought to follow (a) that anyone who uses it will have better teeth than the same person would have if he did not use it; and (b) that if anyone begins to use it his teeth will improve.”

--Mere Christianity, book 4, ch. 10