Guarding Your Mind
Our minds control everything. They influence our thoughts that affect our feelings, and our feelings affect our actions. It all starts in the mind. You are not responsible for every little stray thought that flits or passes through your mind from conversations you overhear by accident or things that you see by accident. What you are responsible for are the thoughts you choose to hold on to and go over and over in your mind. This is an area of irresponsibility even for many long-time Christians. I know a lot of people who are true believers in Christ, but they're watching trashy TV, listening to trash radio, and reading trashy magazines and novels. Whatever you put into your mind is inevitably going to come out in your behavior and your beliefs. It weakens you and it weakens your values because you've become accustomed to it. When things don't bother you any more that is a warning light that you've already passed the threshold. One of the ways Satan tries to get sin and deviant behavior acceptable is to get you to laugh at it. Once you've laughed, your barriers have lowered. If Satan can get you laughing at something that is wrong or sinful, you've already lost the battle. Sin is not funny. It put Jesus on the cross.
“For as he thinks in his heart, so is he. “Eat and drink!” he says to you, But his heart is not with you.”
Proverbs 23:7 NKJV