If he turn not These verses are usually explained in two ways. The meaning is, that if David's enemies should persevere in their malicious designs against him, there is denounced against them the vengeance which their obstinate wickedness deserves. Accordingly, in the second clause, they supply the name of God,--If he turn not, GOD will whet his sword; [1] as if it had been said, If my enemy do not repent, he shall, at length, feel that God is completely armed for the purpose of maintaining and defending the righteous. If it is understood in this sense, the third verse is to be considered as a statement of the cause why God will thus equip himself with armour, namely, because the ungodly, in conceiving all kinds of mischief, in travailing to bring forth wickedness, and in at length bringing forth deceit and falsehood, directly assail God, and openly make war upon him. But, in my judgment, those who read these two verses in one continued sentence, give a more accurate interpretation. I am not, however, satisfied that even they fully bring out the meaning of the Psalmist. David, I have no doubt, by relating the dreadful attempts of his enemies against him, intended thereby to illustrate more highly the grace of God; for when these malicious men, strengthened by powerful military forces, and abundantly provided with armour, furiously rushed upon him in the full expectation of destroying him, who would not have said that it was all over with him? Moreover, there is implied in the words a kind of irony, when he pretends to be afraid of their putting him to death. They mean the same thing as if he had said, "If my enemy do not alter his purpose, or turn his fury and his strength in another direction, who can preserve me from perishing by his hands? He has an abundant supply of arms, and he is endeavouring, by all methods, to accomplish my death." But Saul is the person of whom he particularly speaks, and therefore he says, he hath made fit his arrows for the persecutors This implies that Saul had many agents in readiness who would willingly put forth their utmost efforts in seeking to destroy David. The design of the prophet, therefore, was to magnify the greatness of the grace of God, by showing the greatness of the danger from which he had been delivered by him. Moreover, when it is here said, if he do not return, returning does not signify repentance and amendment in David's enemy, but only a change of will and purpose, as if he had said, "It is in the power of my enemy to do whatever his fancy may suggest." [2] Whence it appears the more clearly, how wonderful the change was which suddenly followed contrary all expectation. When he says that Saul had prepared the instruments of death for his bow, he intimates that he was driving after no ordinary thing, but was fully determined to wound to death the man whom he shot at. Some, referring the Hebrew word dvlqym doulekim, which we have rendered persecutors, to arrows, have rendered it burning, [3] because it has also this signification; [4] but the translation which I have given is the more appropriate. David complains that he had reason to be afraid, not only of one man, but of a great multitude, inasmuch as Saul had armed a powerful body of men to pursue and persecute a poor fugitive.

Footnotes

1 - This is the view adopted by Hengstenberg in his excellent Commentary on The Psalms. "The apparently coarse manner of expression in our text," says he, "representing God as a warrior equipped with sword and bow, has besides for its foundation the coarseness of sinners, and the weakness of faith on the part of believers, which does not direct itself against the visible danger with pure thoughts of God's controllable agency, but seeks to clothe those thoughts with flesh and blood, and regards the judge as standing over against the sinner, man against man, sword against sword."

2 - "Au reste, quand il est yci parle de se retourner, ce n'est pas pour signifier ce que nous appelons repentance et amendement en son ennemi, mais tant seulement une volonte et deliberation diverse; comme si'il dit qu'il estoit en la puissance de l'ennemi de parfaire tout ce qui luy venoit en la fantasie." -- Fr.

3 - Those who adopt this rendering, support it from the reading of the Septuagint, Vulgate, and Syriac versions, although the Chaldee version reads persecuting; and they generally view the 12th and 13th verses as a representation of God under the image of a warrior ready to shoot his flaming, burning, fiery arrows, against the object to which he is opposed." I read vtslqym urentes, inflammatos; the arrows of the Almighty, (Deuteronomy 32:24.) Languishments of famine, the burnings of the carbuncle, and the bitter pestilence. Schultens, (Proverbs 26:23.) Lightnings are also called God's arrows, (Psalm 18:15,) and represented as the artillery of heaven."--Dr Kennicott's note on this place in his Select Passages of the Old Testament. Hengstenberg takes the same view. His rendering is, He [that is, God] makes his arrows burning. "rlq, to burn. In sieges it is customary to wrap round the arrows burning matter, and to shoot them after being kindled."

4 - "La ou nous avons mis Persecuteurs aucuns le rapportans aux fleches, traduissent Ardentes; pource que le mot Hebrieu emporte aussl ceste signification."--Fr.

If he turn not - If the wicked person does not repent. in the previous verse the psalmist had said that God is angry with the wicked every day; he here states what must be the consequence to the wicked if they persevere in the course which they are pursuing; that is, if they do not repent. God, he says, cannot be indifferent to the course which they pursue, but he is preparing for them the instruments of punishment, and he will certainly bring destruction upon them. It is implied here that if they would repent and turn they would avoid this, and would be saved: a doctrine which is everywhere stated in the Scriptures.
He will whet his sword - He will sharpen his sword preparatory to inflicting punishment. That is, God will do this. Some, however, have supposed that this refers to the wicked person - the enemy of David - meaning that if he did not turn; if he was not arrested; if he was suffered to go on as he intended, he would whet his sword, and bend his bow, etc.; that is, that he would go on to execute his purposes against the righteous. See Rosenmuller in loc. But the most natural construction is to refer it to God, as meaning that if the sinner did not repent, He would inflict on him deserved punishment. The "sword" is an instrument of punishment (compare Romans 13:4); and to "whet" or sharpen it, is merely a phrase denoting that he would prepare to execute punishment. See Deuteronomy 32:41.
He hath bent his bow - The bow, like the sword, was used in battle as a means of destroying an enemy. It is used here of God, who is represented as going forth to destroy or punish his foes. The language is derived from the customs of war. Compare Exodus 15:3; Isaiah 63:1-4. The Hebrew here is," his bow he has trodden," alluding to the ancient mode of bending the large and heavy bows used in war, by treading on them in order to bend them.
And made it ready - Made it ready to shoot the arrow. That is, He is ready to execute punishment on the wicked; or, all the preparations are made for it.

If he turn not - This clause the Syriac adds to the preceding verse. Most of the versions read, "If ye return not." Some contend, and not without a great show of probability, that the two verses should be read in connection, thus: "God is a just Judge; a God who is provoked every day. If (the sinner) turn not, he will whet his sword; he hath bent his bow, and made it ready." This, no doubt, gives the sense of both.

If (k) he turn not, he will whet his sword; he hath bent his bow, and made it ready.
(k) Unless Saul changes his mind, I will die, for he has both the men and weapons to destroy me. Thus considering his great danger, he magnifies God's grace.

If he turn not,.... Not God, but the enemy, or the wicked man, spoken of Psalm 7:5; if he turn not from his wicked course of life, to the Lord to live to him, and according to his will; unless he is converted and repents of his sin, and there is a change wrought in him, in his heart and life; the Septuagint, Vulgate Latin, Arabic, and Ethiopic versions read, "if ye turn not", or "are not converted", an apostrophe to the wicked;
he will whet his sword: God is a man of war, and he is sometimes represented as accoutred with military weapons; see Isaiah 59:17; and among the rest with the sword of judgment, which he may be said to whet, when he prepares sharp and sore judgments for his enemies, Isaiah 27:1;
he hath bent his bow, and made it ready; drawn his bow of vengeance, and put it on the full stretch, and made it ready with the arrows of his wrath, levelled against the wicked, with whom he is angry; which is expressive of their speedy and inevitable ruin, in case of impenitence; see Lamentations 2:4; or "trod his bow", as is the usual phrase elsewhere; see Psalm 11:2; which was done by the feet, and was necessary when the bow was a strong one, as Jarchi on Psalm 11:2; observes; and so the Arabs, as Suidas (g) relates, using arrows the length of a man, put their feet on the string of the bow instead of their hands.
(g) In voce

They are here distinctly pointed out, though by changing the person, a very common mode of speech, one is selected as a representative of wicked men generally. The military figures are of obvious meaning.

He will - God will hasten, and speedily execute his judgments upon him.