When I was fourteen, my mom bought me a nice suit for a wedding I needed to attend. Like, really nice. I’ve kept it all these years, just in case I ever need to dress formally. There’s a problem, though. I’m several inches taller and about forty pounds heavier than I was as a freshman in high school. The sleeves are too short. The pants are too tight. The transformation from scrawny teenager to fully-grown man meant that certain clothes just won’t fit anymore.
Likewise, our spiritual transformation in Christ means that certain things just don’t fit us anymore. As Paul says in Ephesians 5, we once were darkness, but now we are light in the Lord. Consequently, the works of darkness aren’t fitting or proper for us as saints. We must walk as children in the light.
...for at one time you were darkness, but now you are light in the Lord. Walk as children of light...
- Ephesians 4:22-24 (ESV)