The mitzvah of learning Torah does not override the mitzvah of serving in the army in order to rescue Israel from her enemies. The Torah permits certain soldiers to return home before setting off to war, such as one who built a house and did not consecrate it, or planted a vineyard and did not harvest it, or who became engaged but did not marry, but this concerns a “milchemet reshut” (a non-obligatory war for economic gains). However, in a “milchemet mitzvah” (a war to conquer the Land of Israel), or to rescue Israel from an enemy: “Everyone goes out, even a groom from his wedding room, and a bride from her wedding canopy” (Talmud Sotah 44b). This is also how the Rambam ruled (Laws of Kings and Their Wars, 7:4).
The students of Yehoshua bin Nun and King David went out to war and were not concerned about the neglect of Torah study (bittul Torah). As for the angel’s reproof of Yehoshua for being guilty of bittul Torah (negligence in Torah study) (Megillah 3a), that was because at night, when the soldiers weren’t occupied with the war, they should have studied Torah. In regards to fighting in the war itself, they weren’t accused of interrupting their learning.

We have seen in the Bible, however, that when Amasa, one of King David’s army officers, needed to enlist soldiers, he came to the Chachamim and found them studying Torah, and according to the halakha, could not enlist them (Sanhedrin 49a). In that case, the war was a milchemet reshut which does not override Torah study. However, when there is a need to enlist Torah students for a milchemet mitzvah, to rescue Israel from her enemies, one is obligated to close the Gemorot and go off to war. Concerning what is written in the Talmud that Torah scholars do not need protection (Bava Batra 8a), the Gemara is not speaking about war, but rather protection from theft. But when the Nation of Israel requires protection from enemies, it is a mitzvah to come to her rescue, as it says, “You shall not stand on the blood of your neighbor” (Vayikra, 19:17). As far as pikuach nefesh is concerned, when a commandment must be violated to save a life, the mitzvah is first incumbent on the Talmidei Chachamim (Mishna Berura 328:34). Although it is stated in the Gemara, “Talmud Torah is greater than saving lives” (Megilla 16b), the meaning is that its value is greater, but from the aspect of one’s obligation, when there is a mitzvah that cannot be fulfilled by others, every mitzvah overrides the command of Talmud Torah – all the more so in regards to the mitzvah of saving Israel from its enemies.

In the Talmud, Rabbi Eleazar is of the opinion that for having enlisted his students to fight in the war against the four kings, Avraham Avinu received the punishment that his offspring would go into exile and be slaves in Egypt for 210 years (Nedarim 32a). Some people use this to support their claim that students of Torah do not have to serve in the army. However, in that instance, the war was not over the conquest of Eretz Yisrael or saving Israel from its enemies. That’s why it was inappropriate to interrupt their Torah studies, according to Rabbi Eleazar. However, when the war comes to conquer Eretz Yisrael, or save the Jewish People, it is a milchemet mitzvah, and Torah students must close their books to join the fight, just as we find in the time of Yehoshua and King David.

Nevertheless, concerning students who are capable of becoming outstanding talmidei chachamin for the sake of Clal Yisrael, our Rosh Yeshiva, Rabbi Tzvi Yehudah HaKohen Kook, ztz’l, ruled that as long as the army does not need to enlist them, it is better they postpone their induction, and continue to ascend in Torah study, learning in order to teach Torah to the Nation. In this way, they would make a decisive contribution to Israel’s spiritual well-being, in addition to its defense and settlement of the Land, which are both enhanced by the learning of Torah. For Torah study brings blessings to all aspects of the Nation. Rabbi Kook emphasized that this allowance only had value if the learning was conducted out of a sense of great respect toward the soldiers who physically fulfilled the mitzvah of saving Israel and settling the Land, at the risk of their lives, for only in this manner could their learning help uplift the spirit and valor of Clal Yisrael.

A short tale from the life of a great Torah scholar will help illustrate the importance of serving in the army. Rabbi Yitzhak Ze’ev Gustman, of blessed memory, was a Gaon in Torah, among the last of the great scholars of Vilna, who sat on the Beit HaDin of the Gaon, Rabbi Chaim Ozer Grodzinsky. While he himself survived the Holocaust, he lost his only son. Years later, he founded a yeshiva in Jerusalem. Nobel Prize winner, Professor Yisrael Aumann, was a frequent visitor of the Rabbi’s. His son, Shlomo Aumann, a student of the Shalavim Hesder Yeshiva, was killed in the Peace for Galilee War in Lebanon. After the funeral, Rabbi Gustman lingered by the graves of other fallen soldiers, mourning by each one. On the way home in the car, he noted that all of the fallen soldiers were holy. “Even the non-religious soldiers?” one of the passengers asked. Vehemently, Rabbi Gustman answered: “All of them! All of them!” Reaching the neighborhood of Rechavia, the elderly Rabbi requested to pay a shiva call to the Aumann home. Everyone there was in silent mourning. Rabbi Gustman requested to say a few words, and then related that he had had a beautiful young son, Meir, whom the Nazis had killed, along with a truckload of other children, during the Holocaust. As a memorial to his son, he removed the youth’s small shoes and traded them for bread and carrots which he distributed to the starving in the ghetto. “Now I will tell you what is taking place in the World of Truth,” he said to the mourners, raising his voice in emotion. “My Meir is saying to your son Shlomo, ‘Fortunate is your lot, Shlomo! I did not have such a great merit! I did not have the merit to die in battle for the Nation, fighting against the enemies of Israel, in defending the Jewish People. You achieved that incomparable honor!’” Professor Aumann stood up from his cushion on the floor and embraced the Rabbi, saying, “You have comforted me. You have comforted me.”
I heard this story from a doctor who was close to Rabbi Gustman. When his own son received a draft notice, he sought the advice of the distinguished elder, who was respected by all of the religious communities in the city. “What does it say in the Torah of Moshe Rabbeinu?” the doctor asked. “To enlist in the army or not?” Rabbi Gustman answered: “In the Torah of Moshe Rabbeinu, it says, “Your brothers shall go forth to war, and you shall sit here!?” Pacing back and forth in emotion, and raising his fist in the air, he repeated the verse several times, his voice growing stronger and more strident each time. “Your brothers shall go forth to war, and you shall sit here!?”