You have a wonderful influence. Let it be for good, not for evil. They say that you corrupt every one with whom you become intimate, and that it is quite sufficient for you to enter a house for shame of some kind to follow after.

– Oscar Wilde

The Picture of Dorian Gray, Chapter 12. Basil, himself a highly moral person, appeals to his friend Dorian to forsake the path of corruption and evil. He says Dorian has a wonderful influence and urges him to use it for good and not evil.