Do all things without complaining and disputing, that you may become blameless and harmless, children of God without fault in the midst of a crooked and perverse generation, among whom you shine as lights in the world… Philippians 2:14-15
I joined the US Navy right out of high school, and after 2 years of training I was finally assigned to an air squadron aboard the aircraft carrier USS Constellation. While we were at sea, we would frequently run a "lights out" drill. This drill was the practice of running the ship at night with zero lighting on the deck, because at night the human eye can see a single match being lit thirty nautical miles away. A single sailor smoking a cigarette can give away the ships position to an enemy.
In his letter to the church at Philippi, Paul uses that same example in the opposite context: Instead of trying to hide our position in a dark world, Paul encourages us to live our lives in such a way that our life is beam of light shining out in a dark world. In the same way that the beam of a lighthouse guides a ship through the dark into safe harbor, our life should be a light that guides the searching, unsaved soul to Christ.
See, if we live like the world, there's no differentiating factor; We blend right in. It might feel more comfortable to blend in, but the consequence is that the lost person that is looking for hope will never see the path to salvation.
"Lord, help me to be blameless and harmless, reflecting the light of Christ to the dark world around me."