The darkness turned into light.
As a reason for their not lapsing into vices from which they had escaped, the apostle reminds them of the darkness of their pagan condition.
I. THEY WERE ONCE DARKNESS ITSELF. "Ye were sometimes darkness." The phrase is very impressive, for it indicates a moral as well as an intellectual darkness. A hard heart is always linked with a blinded understanding. The two act and react upon each other, becoming alternately cause and effect. Men do not care to retain the knowledge of God in their thoughts, and God, in judgment, gives them over to a reprobate mind. The most enlightened natures of the ancient world were thus "darkness" itself. Athens, the eye of Greece, inscribed upon an altar the confession of its ignorance. The phrase, "darkness," suggests three thoughts.
1. There is fear in darkness—the fear of enemies, the fear of death, the fear of undefined agencies. Heathenism was full of fears. Death was a dark and terrible specter.
2. There is discomfort in darkness. Light, its opposite, is the symbol of joy.
3. There is danger in darkness. Enemies use the nights for their deeds of violence. We stumble on a dark night; we fall down precipices; we take a wrong road. How expressive is the term as applied to the heathen!
II. THEY ARE SOW "LIGHT IN THE LORD." Conversion has wrought a radical change in the understanding as well as the heart. Believers are now light "in fellowship with the Lord" (1 John 1:3). There is more implied than the flashing into a human mind the knowledge of the truth; there is the renewing of that mind into the love of the truth which it knows. Otherwise the light would torment and not comfort. But believers, thus doubly furnished may well be called "light in the Lord." The light of the sun does not stream down directly upon the world; at least, it comes to the service of men reflected from a thousand objects which receive it upon their surfaces; similarly the world sees the glory of the Sun of righteousness reflected in the millions of saints who are "lights in the Lord."
III. THE DUTY OF BELIEVERS IN THESE CIRCUMSTANCES—"WALK AS CHILDREN OF LIGHT." That is, as those in nearest connection with it.
1. As light signifies joy, believers walk in the joy of an assured hope and a perpetual cleansing. "If we walk in the light, as he is in the light, .. the blood of Jesus Christ his Son cleanseth us from all sin" (1 John 1:7).
2. We walk in the day and therefore should not stumble. "The darkness is past, and the true light now shineth" (1 John 2:8). We ought to keep an eye fixed on the straight path of duty, and avoid the by-paths that lead to darkness and ruin.
3. If we walk in the light, we ought clearly to recognize the fellowship of all travelers to Zion. "If we walk in the light .. we have fellowship one with another." We are going the same way, inspired by the same hopes, meeting the same difficulties, arriving at last at the same home.—T.C.