I got this from an old Revive Our Hearts podcast. To view the transcript for the entire podcast which is an interview with Joshua Harris on the effects of media, go
here. (It's really good, BTW!)
Joshua: When John Wesley was in college, he wrote a letter to his mom asking the question, “What is sin?” I think he was looking for a catalog of activities.
Nancy: “The list.”
Joshua: Exactly; a list. I can imagine somebody listening to this about media, saying something like, “Okay, well, tell me what I’m not allowed to watch. Kind of give me a …”
Nancy: We’re not going to do that.
Joshua: Exactly. And neither did she. Mrs. Wesley wrote him back, and I just want to read what she said. I think it’s so wise. She said,
Take this rule: Whatever weakens your reason, impairs the tenderness of your conscience, obscures your sense of God, or takes off the relish of spiritual things; in short, whatever increases the strength and authority of your body over your mind, that thing is sin to you, however innocent it may be in itself.