Fret not thyself because of the wicked. David lays down this as a general principle, that the prosperity of the wicked, in which they greatly rejoice, should on no account vex or disquiet the children of God, because it will soon fade away. On the other hand, although the people of God are afflicted for a time, yet the issue of their afflictions shall be such, that they have every reason to be contented with their lot. Now all this depends upon the providence of God; for unless we are persuaded that the world is governed by him in righteousness and truth, our minds will soon stagger, and at length entirely fail us. David then condemns two sinful affections of the mind, which are indeed closely allied, and the one of which is generated by the other. He first enjoins the faithful not to fret on account of the wicked; and, secondly, that they should not indulge an envious spirit towards them. For, in the first place, when they see the wicked enjoying prosperity, from which it might naturally be supposed that God regards not the affairs of men, there is a danger lest they should shake off the fear of God, and apostatise from the faith. Then another temptation follows, namely, that the influence of the example of the wicked excites in them a desire to involve themselves in the same wickedness with them. This is the natural sense. The Hebrew words, 'l-ttchr, al-tithechar, which we have rendered, Fret not thyself, are by some translated, Do not mingle thyself with. [1] But this interpretation is too forced, and may be disproved by the context; for in the eighth verse, where mention is expressly made of wrath and anger, it would surely be absurd to interpret in another sense the same verb which immediately follows these two words, and which is there used in the same sense and for the same end as in this first verse. In the second place, the order which David observes is very natural; for when the prosperity of the wicked has irritated our minds, we very soon begin to envy them their happiness and ease. First, then, he exhorts us to be on our guard, lest a happiness which is only transitory, or rather imaginary, should vex or disquiet us; and, secondly, lest envy should lead us to commit sin. The reason by which he enforces this exhortation is added in the following verse: for if the wicked flourish to-day like the grass of the field, to-morrow they shall be cut down and wither. We need not wonder that this similitude is often to be met with in the sacred writings, since it is so very appropriate; for we see how soon the strength of the grass decays, and that when cast down by a blast of wind, or parched with the heat of the sun, even without being cut by the hand of man, it withers away. [2] In like manner, David tells us that the judgment of God, like a scythe in the hand of man, shall cut down the wicked, so that they shall suddenly perish.

Footnotes

1 - That is, do not enter into fellowship with.

2 - The fitness of this figure to express the transient and short-lived character of the prosperity of the wicked, will appear in a still more striking light when we take into consideration the great heat of the climate of Palestine.

Fret not thyself - The Hebrew word here means properly to burn, to be kindled, to be inflamed, and is often applied to anger, as if under its influence we become "heated:" Genesis 31:36; Genesis 34:7; 1-Samuel 15:11; 2-Samuel 19:43. Hence, it means to fret oneself, to be angry, or indignant. Compare Proverbs 24:19. We should perhaps express the same idea by the word "worrying" or "chafing." The state of mind is that where we are worried, or envious, because others are prosperous and successful, and we are not. The idea is, therefore, closely allied with that in the other part of the verse, "neither be thou "envious.""
Because of evil-doers - Wicked men:
(a) at the fact that there are wicked men, or that God suffers them to live;
(b) at their numbers;
(c) at their success and prosperity.
Neither be thou envious - Envy is pain, mortification, discontent, at the superior excellence or prosperity of others, accompanied often with some degree of malignant feeling, and with a disposition to detract from their merit. It is the result of a comparison of ourselves with others who are more highly gifted or favored, or who are more successful than we are ourselves. The feeling referred to here is that which springs up in the mind when we see persons of corrupt or wicked character prospered, while we, endeavoring to do right, are left to poverty, to disappointment, and to tears.

Fret not thyself because of evil doers - It is as foolish as it is wicked to repine or be envious at the prosperity of others. Whether they are godly or ungodly, it is God who is the dispenser of the bounty they enjoy; and, most assuredly, he has a right to do what he will with his own. To be envious in such a case, is to arraign the providence of God. And it is no small condescension in the Almighty to reason with such persons as he does in this Psalm.

"[A Psalm] of David." Fret not (a) thyself because of evildoers, neither be thou envious against the workers of iniquity.
(a) He admonishes us neither to vex ourselves for the prosperous estate of the wicked, or to desire to be like them to make our estate better.

Fret not thyself because of evildoers,.... The saints may be grieved at them and for them, because of their evil doings, and may be angry with them for them; yet are not to show any undue warmth, at least in an indecent way, by calling them opprobrious names; for the words may be rendered, "do not show thyself warm" or "angry" (i): in a sinful way; or fret not at their outward prosperity, as it is explained Psalm 37:7. The Targum adds, "to be like them", which agrees with Psalm 37:8;
neither be thou envious against the workers of iniquity; that is, at their present temporal happiness; see Psalm 73:3. The Targum adds, as before, to be joined with them; which sense some parallel places seem to incline to, Proverbs 3:31.
(i) "ne accendaris ira", Junius & Tremellius; "ne exardescas", Gejerus, Michaelis.

When we look abroad we see the world full of evil-doers, that flourish and live in ease. So it was seen of old, therefore let us not marvel at the matter. We are tempted to fret at this, to think them the only happy people, and so we are prone to do like them: but this we are warned against. Outward prosperity is fading. When we look forward, with an eye of faith, we shall see no reason to envy the wicked. Their weeping and wailing will be everlasting. The life of religion is a believing trust in the Lord, and diligent care to serve him according to his will. It is not trusting God, but tempting him, if we do not make conscience of our duty to him. A man's life consists not in abundance, but, Thou shalt have food convenient for thee. This is more than we deserve, and it is enough for one that is going to heaven. To delight in God is as much a privilege as a duty. He has not promised to gratify the appetites of the body, and the humours of the fancy, but the desires of the renewed, sanctified soul. What is the desire of the heart of a good man? It is this, to know, and love, and serve God. Commit thy way unto the Lord; roll thy way upon the Lord, so the margin reads it. Cast thy burden upon the Lord, the burden of thy care. We must roll it off ourselves, not afflict and perplex ourselves with thoughts about future events, but refer them to God. By prayer spread thy case and all thy cares before the Lord, and trust in him. We must do our duty, and then leave the event with God. The promise is very sweet: He shall bring that to pass, whatever it is, which thou has committed to him.

A composed and uniform trust in God and a constant course of integrity are urged in view of the blessedness of the truly pious, contrasted in various aspects with the final ruin of the wicked. Thus the wisdom and justice of God's providence are vindicated, and its seeming inequalities, which excite the cavils of the wicked and the distrust of the pious, are explained. David's personal history abundantly illustrates the Psalm. (Psalm. 37:1-40)
The general sentiment of the whole Psalm is expressed. The righteous need not be vexed by the prosperity of the wicked; for it is transient, and their destiny undesirable.

Olshausen observes, "The poet keeps entirely to the standpoint of the old Hebrew doctrine of recompense, which the Book of Job so powerfully refutes." But, viewed in the light of the final issue, all God's government is really in a word righteous recompense; and the Old Testament theodicy is only inadequate in so far as the future, which adjusts all present inconsistencies, is still veiled. Meanwhile the punitive justice of God does make itself manifest, as a rule, in the case of the ungodly even in the present world; even their dying is usually a fearful end to their life's prosperity. This it is which the poet means here, and which is also expressed by Job himself in the Book of Job, Job 27:1. With התחרה, to grow hot or angry (distinct from תּחרה, to emulate, Jeremiah 12:5; Jeremiah 22:15), alternates קנּא, to get into a glow, excandescentia, whether it be the restrained heat of sullen envy, or the incontrollable heat of impetuous zeal which would gladly call down fire from heaven. This first distich has been transferred to the Book of Proverbs, Proverbs 24:19, cf. Proverbs 23:17; Proverbs 24:1; Proverbs 3:31; and in general we may remark that this Psalm is one of the Davidic patterns for the Salomonic gnome system. The form ימּלוּ is, according to Gesenius, Olshausen, and Hitzig, fut. Kal of מלל, cognate אמל, they wither away, pausal form for ימּלוּ like יתּממוּ, Psalm 102:28; but the signification to cut off also is secured to the verb מלל by the Niph. נמל, Genesis 17:11, whence fut. ימּלוּ = ימּלּוּ; vid., on Job 14:2; Job 18:16. ירק דּשׁא is a genitival combination: the green (viror) of young vigorous vegetation.

Fret not - Because they prosper in their wicked enterprizes.