The Torah instructs, “When you go out to battle against your enemy, and see horse and chariot – a nation more numerous than you – you shall not fear them, for Hashem your G-d, who brought you up from the land of Egypt, is with you. It shall be that when you draw near to battle, the Kohen shall come forward and speak to the people. He shall say to them, ‘Hear, O Israel! You are coming near to battle against your enemy. Let not your heart be faint. Do not be afraid, do not panic, and do not be broken before them. For it is Hashem your G-d who goes with you, to do battle for you against your enemy, to save you’” (Devarim 20:1-4).
According to the Rambam, the Torah prohibits the Jewish soldier to exhibit fear when facing his enemies (Sefer HaMitzvot, negative command 58; Hilchot Melachim 7:15. See also Semag, negative command 231; Sefer HaChinuch 525; Rashi to Devarim 20:3). The Rambam (Sefer HaMitvot, ibid.) cites additional verses where the Torah repeats the prohibition, “You shall not be broken before them” (Devarim 7:21) and “You shall not fear them” (Devarim 3:22).
But according to the Ra’avad and Ramban, there is no Torah prohibition to fear. Instead, the Torah promises the soldier that he will not fear (See their comments to the Rambam’s Sefer HaMitzvot).
The Ramban adds that the Torah (Devarim 20:8) exempts one who is fearful from fighting in the first place in a Milchemet Reshut, an optional war waged to increase the boundaries of Israel: “The officers shall continue speaking to the people and say, ‘Who is the man who is fearful and fainthearted?’ Let him go and return to his house, and let him not melt the heart of his fellows, like his heart’” (Devarim 20:8). The Ramban asks, if it is indeed prohibited to fear, why would the Torah allow for such exemptions?
Meshech Chachmah (Devarim 20:3) explains that prohibition is to fear during battle. Therefore, exemptions before entering the battlefield are permitted. The Steipler Gaon (Kehilat Ya’akov 1:34) distinguishes between different types of fear. Fear, after all, is a normal human emotion. There is a natural fear which any sensible person would experience when going off to war. What the Torah prohibits, according to the Steipler, is a fear rooted in a lack of faith in Hashem; Fearing “horse and chariot” and “a nation more numerous than you,” instead of a firm belief that “Hashem your G-d who goes with you, to do battle for you against your enemy, to save you” (See also Sha’arei Teshuvah, 3:31-32).
Even according to the Rambam, the nature of the prohibition is unclear. In his Mishneh Torah, the Rambam writes, “Anyone who begins to feel anxious and worry in the midst of battle to the point where he frightens himself, violates a negative commandment” (Hilchot Melachim, ibid.). But in his Sefer HaMitzvot, he writes, “Anyone who retreats and runs away has violated a negative commandment” (Sefer HaMitzvot, ibid). It would appear that according to the Rambam, one only violates this prohibition by expressing fear through causing himself to panic or by retreating in battle (See Minchat Chinuch, Kometz Mincha 525; Rav Perlow’s Commentary to the Sefer HaMitzvot of Rav Sa’adiah Ga’aon, negative command 128; Sefer Maharam Schick al Taryag Mitzvot).
The Mishna (Sotah 8:6) even instructs armed guards to be stationed at the front and rear of the soldiers, to prevent soldiers from fleeing the battlefield. A soldier exhibiting fear or fleeing may cause his fellow soldiers to panic, and will be responsible for their deaths. He can also jeopardize the outcome of the battle (See Hilchot Melachim, ibid.).
Instead, the Jewish soldier is commanded to trust in Hashem. As the Rambam writes:
“Once a soldier enters the throes of battle, he should rely on the Hope of Israel and their Savior in times of distress. He should realize that he is fighting for the sake of the oneness of Hashem’s Name. Therefore, he should place his soul in his hand and not show fright or fear. He should not worry about his wife or children. On the contrary, he should wipe their memory from his heart, removing all thoughts from his mind except the war… Anyone who fights with his entire heart, without fear, with the intention of sanctifying Hashem’s name alone, can be assured that he will find no harm, nor will bad overtake him. He will be granted a proper family in Israel and gather merit for himself and his children forever. He will also merit eternal life in the World to Come…” (Hilchot Melachim, ibid.).
May our brave and holy soldiers place their trust in Hashem, and may He protect them and grant them success. Amein.