Eph 5:16 redeeming the time, because the days are evil.
The expression "redeeming the time" is literally "buying up the opportunities" in the Greek.
Paul commanded the Ephesians walk in the light (verse 8) and the need to be up and about and alert in doing it (verse 14). The days are evil and the opportunity to shine is now. Believers are to take advantage of it. Seize it. Make most of the opportunity. They are to shine and not lose the opportunity in doing it. Every opportunity is precious. It should not be mishandled and lost.
Walking in the light is walking in Christ-likeness. It is exhibiting Christ to the world.
