TT #284 · Parashas Shoftim · Seventh Aliyah · Passuk 20:05
And the officers shall speak to the people, saying: Who is the man who has built a new house and has not dedicated it? Let him go and return to his house, lest he die in the battle and another man dedicate it.
Torah Temimah points to Sotah 43a / Sifrei.
TT lemma: מִי הָאִישׁ אֲשֶׁר בָּנָה בַיִת חָדָשׁ.
English: ‘Who is the man who has built a new house and has not dedicated it’ – he shall return.
Derash on the house exemption (Bavli / Sifrei) — a new house not yet dedicated frees a man from combat.
A man who has built a new house and has not yet dedicated it is sent home from the battle lines.