It says מגן אם יראה ורמח בארבעים אלף ישראל, was even a shield or a spear seen among 40,000 in Israel.
The Tanna Dvei Eliyahu comments that 40,000 from the Jewish people go out to war and there is amongst them one pair of Torah scholars, it is like they are holding a shield and a double-edged sword. R' Asher Weiss explains that a מגן, shield is a defensive weapon while a רמח, spear is an offensive weapon. An army invests in offense and defense in order to be victorious. Corresponding to this is the Milchamta Shel Torah. In Torah the one asking the question is the one on the offensive and the one answering is on the defense. In this way the Milchamta Shel Torah provides strength to the soldiers.
Shoftim 5:8.
Chapter 10.
Milchamta Shel Torah can also remove war. Through engaging in Torah which is like fighting, as in fact it is called Milchamta Shel Torah, other fighting (wars and the like) can be removed, thereby increasing peace in the world. This explains the dictum that Torah scholars increase peace in the world since through the Machlokes of Torah, there can be more peace in the world.
Drashos Chassam Sofer, p. 806.
