Charles H. Spurgeon on Psalms 17:13

"The wicked, which is thy sword." The devil and his instruments both are God's instruments, therefore "the wicked" are called his "sword," his "axe" (Psalm 17:13; Isaiah 10:15); now let God alone to wield the one, and handle the other. He is but a bungler that hurts and hackles his own legs with his own axe; which God should do if his children should be the worse for Satan's temptations. Let the devil choose his way, God is a match for him at every weapon. If he will try it by force of arms, and assaults the saints by persecution, as the "Lord of hosts" he will oppose him. If by policy and subtlety, he is ready there also. The devil and his whole council are but fools to God; nay, their wisdom foolishness. —William Gurnall.