Keep thy heart with all diligence! Here is a paradox! We are commanded to do what we cannot, for no one can keep his own heart. “The greatest difficulty in conversion is to win the heart to God, and after conversion to keep it with Him” (Flavel). It is God’s work, but “our efforts are His instrumentality. He implants an active principle, and sustains the unceasing exercise” (Bridges). We know thoughts shape our character and conduct. Paul’s appeal in Romans 12:1-2 is to every faithful soldier on the Bulwarks.

One cannot miss the stark contrast between verses 18 and 19, between a path of shining light and another of deepest darkness, between expanding joy or advancing danger (Matt. 6:22-23)! The word darkness used here is the same as in Exodus 10:22 to describe the supernatural darkness of God’s judgment. While it may not be entirely correct to suggest that the Devil is an ass, it is assuredly true of the dupes who follow him! Sin is a dark path, even darkness itself, and carries with it the idea of evil and misery. Sin is, after all, a fatal attraction.

The perfect day, and what a day of rejoicing that will be! “As the sun climbs the heavens, shining brighter and brighter, from the first faint glimmer of dawn till he reaches his meridian height and appears to stand there firm and motionless; so is the path of the righteous. His sun standeth still at last in the heavens, and hasteth not to go down for the whole everlasting day” (Perowne). Then shalt the righteous (the just) shine forth as the sun in the Kingdom of their Father (Mt. 13:43; Rev. 21:23-27). What a truly glorious culmination for the just!

Here is one of those precious gems in our Authorised Version. It is God’s path, not the path of the just, that is here compared to the sun’s movement across the heavens. Arnot makes the vital distinction, that the sun is a figure, not of the justified but of the Justifier. This grandest object is used to describe the Highest in all His glory. Christ is the Light, and Christians are but the reflectors. “The just,” says Arnot, “are those whom the Sun of Righteousness shines upon. They who were once darkenss are light not, but it is ‘in the Lord.’” What a blessing to know that one is walking by the Light of the World!

We now must take a closer look at the path of the wicked and those who travel it. The wicked have their path. It is very broad and very winding. It is popular today to reject negative virtue, but there can be no positive virtue without it. “Negative virtue is not good enough; we must do good” (William S. Plumer). How can the guilt-ridden love themselves unless and until they face the reasons for their anger and hate? Wisdom sounds a fervent warning here declaring that “virtue is the only true nobility”.

Again, we find two opposite paths presented in our verses today, the path of Wisdom and the path of wickedness. Jesus called them the Broad way to Destruction and the Narrow to Life. There can be no neutrality. The unregenerate man makes loud claims to know right, but Paul declares, in spite of all his claims and confidence, he will not accept the Bible’s teaching (1 Cor. 1:20-21; 2:11-14). We must be for the right, but it must be the right as defined by God, who alone can define it.

The rewards and benefits of Wisdom are not a matter of vain speculation as demonstrated in these verses. Those who possess this Wisdom will be forever enriched through its special benefits. Matthew Henry comments here, “A soul without true wisdom and grace is a dead soul. How poor, how contemptible and wretched are those, who, with all their wealth and power, die without getting understanding, without Christ, without hope, and without God.”