Be Sensitive to Sin
Warning: the following story may contain graphic descriptions of a disturbing nature.
When I was in high school, the room where I took biology was the same room that the anatomy class met in the period before. Midway through the school year, they began studying the skeletal system by ... wait for it ... boiling the flesh off of deceased cats in slow cookers! One slow cooker and cat per student. You can imagine the intensely putrid smell filling the room (and the whole building)! While we all complained, "This is cruel and unusual punishment," that's when we learned a lesson about our olfactory systems.
Odor habituation, or "noseblindness," is your body's way of getting used to offensive odors. Your brain reprograms itself to ignore the smell! Amazingly, none of us were able to detect the foul feline funk in the room mere minutes after class began.
"They have become callous and have given themselves up to sensuality, greedy to practice every kind of impurity" (Eph. 4:19).
Paul describes a similar condition of the heart when speaking about those who walk in their sins. As offensive as their actions might seem at first, eventually they become callous and unfeeling towards that lifestyle. A similar term used in the verse before is "hardness of heart," or a reprogramming of the heart to ignore sin and its effects. While "noseblindness" might be a positive response in a high school biology classroom, it's not something we want happening in our daily walk with Christ. So, how do we avoid becoming desensitized to sin?
Put Off Your Old Self
First, we need to distance ourselves from evil practices. In his letter to the Colossians, Paul lists some of these problematic behaviors we must push aside, "But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth" (Col. 3:8). Constant exposure will eventually lead to acceptance and normalization. What evil have you grown callous to in your own heart?
Renew Your Mind
Renewal is about making something new and better. Our minds need to be rebooted like a computer that's been acting strangely — advice nerds have been giving to family and friends for years. When our minds are functioning correctly and trained by God's will, we'll know what's right from what's wrong (Rom. 12:2). Are you in the word, allowing it to reprogram your way of thinking to become better?
Put On The New Self
The Creator himself designs this new life to which he calls us. Paul says that this new way of living is characterized by "true righteousness and holiness" (Eph. 4:24) — implying that we don't get to define it for ourselves. And God has clearly shown us what is right and how to be holy by pointing us to the perfection of Jesus. Are you walking as he walked, speaking as he spoke, and thinking how he thought?