Reasons for the Exemption

The Mishna states: One, who builds a house, betroths a woman or plants a vineyard is exempt from going to battle.

There are various reasons to explain these exemptions: The Rashbam states: These people are similar to the ones who are faint of heart. They are concerned that they will not merit inaugurating their house, marrying their wife or redeeming their vineyard. They are scared that they will die during battle and are therefore exempt from going to war.

The Ibn Ezra explains: These people are preoccupied with their desire to inaugurate their house, marrying their wife or redeeming their vineyard, and will therefore not pay attention completely to the war. This will cause them to retreat during the heat of the battle and will constitute a danger to the remainder of the army.

The Mishna enumerates all the various people that may return from the battle. The Minchas Chinuch (§ 526) writes that it is not clear from the Gemora or the Rambam if these people have the option of remaining at the battlefield or not. He states that it is logical to assume that the faint of heart are required to go home, for otherwise, he will cause the hearts of the others to melt. He adds that according to Rashi, who writes that these people will definitely die during the war if they do not heed the words of the Kohen, they would not have the option of staying.

Seemingly, according to the reasons mentioned above, they would not be allowed to remain at the battlefield, for according to the Rashbam, they are similar to the faint of heart, and they are required to go home. And according to the Ibn Ezra, they would also be required to return home, for otherwise, they would constitute a danger to the other soldiers.