Albert Barnes Commentary Zechariah 9:15

"Jehovah of hosts will defend them; and they shall devour, and shall tread down the sling-stones; and they shall drink, and make a noise as through wine; and they shall be filled like bowls, like the corners of the altar." — Zechariah 9:15 (ASV)

The Lord of hosts, will defend them - As God says, “I will defend this city to save it, for Mine own sake and for My servant David’s sake.” The word is used by Isaiah only before Zechariah, and of the protection of Almighty God. The image of the complete protection on all sides stands first in God’s words to Abraham, “I am thy shield” (Genesis 15:1); David therefore says to God, “Thou, O Lord, art a shield around me” (Psalms 3:4, Psalms 3:3 in English).

And they will devour, and subdue - Or more probably (as in the margin), “shall tread on, the stones of the sling,” as in the image of leviathan in Job: “The son of the bow will not make him flee; sling-stones are to him turned into stubble; clubs are counted as stubble; he laugheth at the shaking of a spear” (Job 41:20–21, Job 41:28–29 in English). Their enemies will fall under them, as harmless and as of little account as the slingstones which have missed their aim, and lie as the road to be passed over.

It is not expressed what they will devour, and so the image is not carried out, but left indefinite, signifying destruction or absorption only. This is exemplified when Scripture says, “thou shalt consume (literally, eat) all the people which the Lord thy God shall deliver thee” (Deuteronomy 7:16); and, “they are our bread” (Numbers 14:9); and again, when it says, “they shall devour (literally, eat) all the people round about” (Zechariah 12:6), where the image is of fire, not of eating.

The one thought seems to be that their enemies should cease to exist, so as to molest them any more, whether by ceasing to be their enemies or by ceasing to be. There is no comparison here (as in Balaam) with the lion, or of eating flesh or drinking blood, which, apart from the image of the wild beast, would be intolerable to Israel, to whom the use of blood, even of animals, was so strictly forbidden. They should disappear as completely as fuel before the fire, or food before the hungry. The fire was invigorated, not extinguished, by the multitude of the fuel: the multitude of the enemies but nerved and braced those whom they sought to destroy.

And they will be filled like bowls, like the corners of the altar - They will be consecrated instruments of God; they will not prevail for themselves, but for Him. They will be hallowed like the bowls of the temple, from which the sacrificial blood is sprinkled on His altar, or as the corners of the altar which receive it.