Arise, O Lord - See the notes at Psalms 3:7.
Disappoint him - Margin, “prevent his face.” The marginal reading expresses the sense of the Hebrew. The word used in the original means “to anticipate, to go before, to prevent;” and the prayer here is that God would come “before” his enemies; that is, that he would cast himself in their way “before” they should reach him. The enemy is represented as marching upon him with his face intently fixed, seeking his destruction; and he prays that God would interpose, or that He would come to his aid “before” his enemy should come up to him.
Cast him down - That is, as it is in the Hebrew, make him bend or bow, as one who is conquered bows before a conqueror.
Deliver my soul from the wicked - Save my life; save me from the designs of the wicked.
Which is thy sword - The Aramaic Paraphrase renders this, “Deliver my soul from the wicked man, who deserves to be slain with thy sword.” The Latin Vulgate: “Deliver my soul from the wicked man; thy spear from the enemies of thy hand.” So the Septuagint: “Deliver my soul from the wicked; thy sword from the enemies of thy hand.” The Syriac, “Deliver my soul from the wicked, and from the sword.” DeWette renders it, “Deliver my soul from the wicked by thy sword.” Prof. Alexander, “Save my soul from the wicked (with) thy sword.” So Luther, “With thy sword.” The Hebrew will undoubtedly admit of this latter construction, as in a similar passage in Psalms 17:10; and this construction is found in the margin: “By thy sword.” The sentiment that the wicked ARE the “sword” of God, or the instruments, though unconsciously to themselves, of accomplishing his purposes, or that he makes them the executioners of his will, is undoubtedly favored by such passages as Isaiah 10:5-7 (see the notes at those verses), and should be properly recognized. But such a construction is not necessary in the place before us, and it does not well agree with the connection, for it is not easy to see why the psalmist should make the fact that the wicked were instruments in the hand of God in accomplishing his purposes a “reason” why He should interpose and deliver him from them. It seems to me, therefore, that the construction of DeWette and others, “Save me from the wicked “by” thy sword,” is the true one. The psalmist asked that God would interfere by his own hand, and save him from danger. The same construction, if it be the correct one, is required in the following verse.