The start of every day includes preparation. We do not usually wear our pajamas (or lack thereof) to work. It’s a good idea to head into your day with all the things that help you to be awake. It’s toothbrush time and making yourself presentable time.
In the analogy of night and day, sleep, and slumber; there are counterproductive attitudes and behaviours that make us unpresentable. A disheveled partier with a hangover does not present well in the morning when the light comes up. The person who has spent their night in an impure way, is not fully present at the breakfast table with his or her family. They are held back by their secrets and their shame.
Paul is telling the church that their former life was filled with darkness, but that’s supposed to be over now. They are living in the hope of Christ’s new day and the need to be ready for that.
In verse 14 he instructs them to put on the Lord Jesus Christ, as if he were there clothing. In other words, now that you claim to be awake it is time to get dressed in what the day requires.
The coming day of the Lord requires that we dress like Jesus. Not a robe and sandals per se but having a presentable appearance that is characterized by His light and goodness. Your night clothes do not suit the day that you are preparing for.
Let us act as we should, like people living in the daytime…
Putting on Christ is not an insincere mask; it is an immersion in imitating the good that you see. You become hidden in Christ. So, are you just acting then? The difference between a skilled actor and a second rate one is in their ability to ‘become’ the character that they portray. Perhaps our understanding of discipleship needs to appropriate this kind of character development.
May we be known for our realistic portrayal of the one we follow and love completely.
 Romans 13:13a