Ellicott's Commentary for English Readers
When thou goest out to battle against thine enemies, and seest horses, and chariots, and a people more than thou, be not afraid of them: for the LORD thy God is with thee, which brought thee up out of the land of Egypt.XX.
LAWS OF WARFARE.
(1) When thou goest out to battle—i.e., generally; not only in the immediate conquest of Canaan. Yet it may be observed that in the writings of Moses it is foreseen that the completion of the conquest will be gradual, and that Israel will have to go to battle many times before all enemies are overcome.
Horses and chariots.—The Israelitish army was chiefly, or rather entirely, composed of infantry, in most of the great victories won by them.
And it shall be, when ye are come nigh unto the battle, that the priest shall approach and speak unto the people,(2) The priest.—There is no mention of the Levite here. The priest is named as a distinct personage. The words which the priest are to pronounce are, as it were, the blessing of Jehovah on the campaign. It follows that Israel could not lawfully go to war except when the blessing of Jehovah might be invoked.
And shall say unto them, Hear, O Israel, ye approach this day unto battle against your enemies: let not your hearts faint, fear not, and do not tremble, neither be ye terrified because of them;(3) Let not your hearts faint, fear not.—In these words Isaiah strengthened Ahaz (Deuteronomy 7:4): “fear not, neither be faint-hearted.”
Be ye terrified.—A strong word. The idea is, “do not even be unnerved, much less alarmed, at the sight of them.”
For the LORD your God is he that goeth with you, to fight for you against your enemies, to save you.(4) For the Lord your God is he that goeth with you.—“They come in the might of flesh and blood; but ye come in the might of the Eternal” (Rashi). So David to Goliath: “Thou comest to me with a sword and with a spear, and with a shield; but I come to thee in the name of the Lord of Hosts, the God of the armies of Israel, whom thou hast defied” (1Samuel 17:45). And so the Psalmist: “Some trust in chariots, and some in horses: but we will remember the name of the Lord our God” (Psalm 20:7).
And the officers shall speak unto the people, saying, What man is there that hath built a new house, and hath not dedicated it? let him go and return to his house, lest he die in the battle, and another man dedicate it.(5) And the officers.—The shôterim of Deuteronomy 16:18; the civil magistrates apparently. The organisation of Israel was not military, but military leaders were to be appointed for special services, as appears by Deuteronomy 20:9, “they shall make captains of the armies.” The captains of thousands, hundreds, fifties and tens were called shôterim (Deuteronomy 1:15).
(5-8) What man is there . . .—These questions show that, primarily, all Israelites of military age (20 to 50) were expected to attend the muster; then those who were unprepared for the campaign were suffered to depart. The only recorded instance of the observance of these rules is in Judges 7:3, at the muster of Gideon’s army. The proclamation “Whosoever, is afraid let him depart,” sent away 22,000 out of 32,000 on that occasion, or rather more than two-thirds of the army!
And it shall be, when the officers have made an end of speaking unto the people, that they shall make captains of the armies to lead the people.(9) Captains of the armies—i.e., special leaders for the campaigns, whose command would probably cease when it was over. We may suppose from mention of the “thousands” in the army—“the captain of their thousand” (1Samuel 17:18)—that the military divisions corresponded with the civil organization of the people so far as this, that the men of the same “thousand,” according to Jethro’s arrangement, would be brigaded together, and have one captain. If, as is also possible, the word “thousand” in military language signifies the contingent furnished by a “thousand” in Israel, irrespective of its number, it would remove many difficulties; for the whole thousand would very rarely be in the field together, and the contingent sent by a given “thousand” might consist of a very few men. If, therefore, the contingent of sixty “thousands” were to be described as 60,000, and the sixty companies were all cut up or annihilated, it might be reported as a slaughter of 60,000 men, while the lives actually lost would be nothing like so many.
When thou comest nigh unto a city to fight against it, then proclaim peace unto it.Deuteronomy 20:10-20. SIEGES.
(10) When thou comest nigh . . . proclaim peace.—Not as the children of Dan did, who massacred the inhabitants of Laish without warning (Judges 18:27-28). Even in the wars of Joshua, the cities that “stood still in their strength” were generally spared (Joshua 11:13).
(15) Thus—i.e., sparing the women and the little ones.
(16-18) But of the cities of these people . . . thou shalt save alive nothing that breatheth . . . that they teach you not to do after all their abominations.—Upon the inhabitants of these cities the Israelites executed the sentence of Jehovah. Their abominations are sufficiently indicated in Leviticus 18:24-28; Leviticus 20:23.
These verses (16-18) are parenthetical; Deuteronomy 20:19 returns to the previous subject.
(19) And thou shalt not cut them down (for the tree of the field is man’s life).—Literally, the passage seems rather to mean this, Is the tree of the field a man, that it should escape thee and enter into the siege? It will not run away and fight in the trenches as a man might do. What need is there to cut it down? This seems to be the view of the Targums, the LXX., and the Jewish commentators, besides modern authorities cited in the Variorum Bible. The destruction of the trees around Jerusalem was a notable feature of the Roman war.