http://www.sichosinenglish.org/books/sichos-in-english/12/17.htm4. In the Song which the Jews sang extolling G-d for His miracles at the splitting of the sea, we find the following verse (Shemos 15:3): “The L-rd is master of war, the L-rd is His Name.” On the words “The L-rd is His Name” Rashi comments: “His wars are not (fought) with weapons, but with His Name He wages war, as Dovid said ‘But I come to you in the Name of the L-rd of hosts.’ Another interpretation: ‘The L-rd is His Name’ — even at the time when He wages war and avenges Himself of His enemies, He retains His attribute of having mercy on His creatures and of sustaining all that enter the world [as indicated by ‘The L-rd is His Name,’ ‘L-rd’ being the attribute of mercy]. And it is not like the nature of earthly kings who, when he (an earthly king] is engaged in war, turns himself away from all (other) matters and there is no strength in him to do both this and that [wage war and attend to other matters].”
There are several points in this Rashi which need clarification.
1) When Rashi offers two interpretations for something (as in this case), it is because the first interpretation does not suffice of itself; there is a particular difficulty in this interpretation — and the second interpretation answers the specific difficulty left unresolved by the first interpretation. On the other hand, the second interpretation is not as close to the plain meaning of the verse as the first, and therefore Rashi brings it only as a second and secondary interpretation. In our case, what is the difficulty in the first interpretation that necessitates Rashi to offer a second interpretation; and why is the second less close to the plain meaning of the verse than the first?
2) Rashi, in his second interpretation, goes to great lengths to explain that G-d’s conduct is different from a mortal king’s. What purpose does this serve?
3) Rashi ends the second interpretation by explaining a mortal king does not do both things since “There is no strength in him to do this and that.” What difference does it make what is the specific reason a mortal king doesn’t do both?
4) Rashi’s commentary is addressed to a five-year-old learning Scripture, especially to those who lived in Rashi’s time and Rashi’s country. Rashi lived in France, and in his times there were many wars between the kings of France and other countries. The five-year-old in those times sees that during war the king still conducted the affairs of the country. If so, how can Rashi say that “an earthly king who, when he is engaged in war, turns himself away from all (other) matters and there is no strength in him to do both this and that” — when the student sees himself that even during war the French kings did simultaneously run the country?!
All of the above will be understood through elucidation of yet another question. Scripture tells us that G-d’s war against the Egyptians was such that (15:1-4) “Horse with its rider He cast into the sea” and “He hurled Pharaoh’s chariots and his army into the sea.” Likewise, we previously learned that (14:28) “The waters returned and they covered the chariots and the horsemen...” If so, when a student learns Rashi’s interpretation of our verse that G-d’ s wars “are not (fought) with weapons, but with His Name He wages war” he is perplexed.
G-d’s war against the Egyptians was waged with the medium of the sea (“He cast into the sea”) — and what difference does it make if the weapon used is a sword and spear or the waters of the sea? The sea is also a weapon; how then can Rashi say that “His wars are not (fought) with weapons”?
A student however, can answer this question from his knowledge of Scripture just learned previously (and hence Rashi need not explain it). This is not the first time that the expression ‘war’ is used in connection to G-d’s vengeance against the Egyptians. Previously it states (14:25): “The Egyptians said: ‘Let us flee from before Yisrael, for the L-rd wages war for them against Egypt.’” This is stated before the drowning of the Egyptians in the sea, and hence this war waged by G-d was not by the means of any weapons (the sea), but with G-d’s Name.
The Egyptians’ statement that ‘Let us flee from before Yisrael for the L-rd wages war for them against Egypt’ was said when (14:24-25) “The L-rd looked to [destroy] the camp of the Egyptians [who were pursuing the Jews after they left Egypt] by means of the pillar of fire and cloud, and He caused confusion in the camp of the Egyptians. And He removed the wheels of their chariots and made them drive with difficulty.” on this Rashi comments that “the pillar of cloud descended and made it (the ground) like clay, and the pillar of fire heated it, and the hooves of their horses were dislocated.” Rashi further continues to explain that “He caused confusion” denotes ‘confusing,’ and that “He removed the wheels of their chariots” means that “Through the power of fire the wheels were burned and the chariots dragged, while those who sat in them reeled and their organs were disjointed.” When the Egyptians saw all these things happening to them, then “The Egyptians said: ‘Let us flee from before Yisrael for the L-rd wages war for them against Egypt.”
This war was not waged with weapons, for the purpose of weapons is to destroy the enemy. In this case, everything that happened (“He caused confusion”, “He removed the wheels” etc.) did not yet destroy the Egyptians (which happened only when they drowned in the sea), but it only confused them — “those who sat in them reeled” and the chariots dragged.” Nevertheless, although the Egyptians were not destroyed, it states “The L-rd wages war for them against Egypt.” And since it was not waged with weapons, we must conclude that it was waged with G-d’s Name. Hence Rashi states that “His wars are not (fought) with weapons, but with His Name He wages war,” meaning, there are two types of war fought by G-d:
1) with weapons, an example being destroying the Egyptians through the sea;
2) with His Name, an example being “He caused confusion in the camp of the Egyptians” and “He removed the wheels of their chariots.”
Rashi then brings proof to this from that which King Dovid said “But I come to you in the Name of the L-rd of hosts.” Rashi prefers to bring this verse as proof and not the verse (Tehillim 20:8): “Some [rely] upon chariots and some upon horses, but we [rely upon and] invoke the Name of the L-rd our G-d,” for in the latter verse there is no indication of the results that follow. Whereas following the verse “But I come to you in the Name of the L-rd of hosts,” Scripture does tell us the results — that Dovid slew Goliath.
Rashi however does not consider this first interpretation sufficient, for our verse states “The L-rd is master of war, the L-rd is His Name. “ If this meant that G-d wages war with His Name, it should have stated “The L-rd is master of war (not with weapons, but) with His Name L-rd,” similar to that said by Dovid “But I come to you in (i.e. with) the Name of the L-rd of hosts.”
Hence Rashi brings a second interpretation that: “‘The L-rd is His Name’ — even at the time when He wages war and avenges Himself of His enemies, He retains His attribute of having mercy on His creatures and of sustaining all that enter the world.” In this interpretation, the words “The L-rd is His Name” are not an explanation of the preceding words “The L-rd is master of war” (as in the first interpretation, that “The L-rd is master of war” through “The L-rd is His Name” — i.e. the L-rd wages war with His Name), but something additional (and separate). Even when “the L-rd is master of war” — “even at the time when He wages war and avenges Himself of His enemies,” simultaneously “The L-rd is His Name” — “He retains His attribute (“L-rd” is the attribute of mercy) of having mercy on His creatures,” by continuing to “sustain all that enter the world.”
In this second interpretation it is clear why it does not state “with His Name L-rd,” and thus the difficulty in the first interpretation is avoided.
A question still remains however. What is the greatness of G-d that he simultaneously sustains His creatures while waging war, when earthly kings also do that — as a child in France in Rashi’s time could see for himself? To answer this question Rashi emphasizes that “it is not like the nature of earthly kings who, when engaged in war, turns himself away from all (other) matters.” A mortal king, when sending troops to fight a war, can still run the country. But when he is “engaged in war” — when he himself is fighting in the war, he must “turn himself away from all (other) matters.” And when he does so, the country is left leaderless and unprovided for, unlike G-d Who does both simultaneously.
One more point still remains perplexing for the five-year-old student learning Scripture. When he is learning in class, the teacher tells him that all his concentration must be upon his studies and nothing else. If so, perhaps this that an earthly king “turns away from all (other) matters” to devote himself entirely to war is not a deficiency, but an admirable trait. Thus Rashi stresses that the reason an earthly king does so is not because he wishes to, but because “There is no strength in him to do both this and that” — he turns away from all other pursuits because he cannot do otherwise. G-d however, can do both.