Military exemptions are granted to individuals at major life milestones to encourage a stable society, agricultural development, and marriage [שד״ל]. The sequence of these exemptions begins with building a house, moves to planting a vineyard, and concludes with betrothal. This progression offers practical guidance for life. A person should first secure financial stability and a home before marrying. However, severe economic hardship allows for adjusting this order to address immediate needs [תורה תמימה].
The exemption focuses on the betrothal stage. This is a binding legal agreement to build a family that has not yet been realized through actual marriage and bringing the wife into the home [ביאור יש״ר, ביאור שטיינזלץ, The Torah]. The rule covers a wide range of unions, such as a bachelor betrothing a widow, a widower betrothing a virgin, or even a woman awaiting a levirate marriage. In the latter case, all brothers must return from the front lines until one marries her [תורה תמימה, אדרת אליהו, רלב״ג]. However, the exemption strictly applies only to legally permitted marriages. Men involved in forbidden unions, or a man remarrying his divorced wife who is not considered a new bride, must remain at the front [הכתב והקבלה, תורה תמימה, צפנת פענח, רלב״ג, אדרת אליהו]. Furthermore, a man who has already completed his marriage is entirely exempt from military duties for a full year, and he is not even required to supply food to the troops [רלב״ג].
Commentators debate whether returning home is a choice or an obligation. Viewing it as a strict requirement prevents soldiers from staying on the battlefield out of shame or fear of being labeled cowards [שד״ל]. A complementary perspective notes that leaving a betrothed wife behind naturally causes a soldier to worry about never establishing his home. He is forced to return so that his personal anxiety does not spread and ruin the morale of the rest of the army [תורה תמימה בשם רשב״ם ואבן עזרא].
The warning of dying in battle sparks a conceptual discussion. One approach suggests that the inherent danger of war can lead to premature death, because moments of extreme peril invite strict heavenly judgment [אבן עזרא, רבנו בחיי, אבי עזר]. Conversely, another approach argues that dying in combat is not a random tragedy but a direct consequence of disobeying the priest's orders. If a soldier refuses the command to return home, that very sin makes him liable to die in battle [רש״י, שפתי חכמים, משכיל לדוד].
These exemptions apply exclusively to optional wars fought for territorial expansion. In a mandatory war, everyone is drafted, including a bride and groom. The inclusion of a bride does not imply that women take up arms, as combat is not their customary role. Instead, it serves as a metaphor for the suspension of wedding celebrations, or it indicates that women assist in the rear by supplying food and water to the fighters [תורה תמימה, ברכת אשר]. Finally, the tragic prospect of another man marrying the betrothed woman establishes a fundamental legal principle. It teaches that a husband's death officially frees his widow to marry someone else [תורה תמימה].