Okay, you've heard the spiel before."You Christians just pick and choose which of the rules in the Bible you're gonna' obey. It's all subjective and muddled. For instance, you condemn homosexuality as a sin but then you ignore all kinds of other Bible commands about the Sabbath or not eating pork. You're just hypocrites."
How do you answer that kind of thing? Well, take a lesson from Tim Keller who has some very clear, very wise advice right here.