Romans 13:12 : The night is far spent, and the day is at hand: let us therefore cast off the works of darkness, and let us put on the armor of light. There are some difficulties in this verse, but its general meaning seems clear enough. Sin and ignorance are both rep-resented as darkness--night. Christians are all more or less under the influence of both. Paul's language in this verse shows this to be so: "Let us therefore cast off the works of darkness." Without the gospel of Christ darkness covered the world but the dark-ness, or night, was far spent, for the full revelation of the gospel was nearing completion. The day--the full light of the gospel--was at hand.
Now men walk in darkness only by choice. Christians have a responsibility. The gospel is light only to those who open their eyes to it. We must cast off the works of darkness, and put on the armor of light. Light of the gospel is the armor; we put that armor on by learning the gospel and cherishing it. The gospel is light to us only in so far as we know its teaching.
In connection with Romans 13:11-14 read 1 Thessalonians 5:7-10.