כִּי֩ יְהוָ֨ה אֱלֹהֶ֜יךָ מִתְהַלֵּ֣ךְ ׀ בְּקֶ֣רֶב מַחֲנֶ֗ךָ לְהַצִּֽילְךָ֙ וְלָתֵ֤ת אֹיְבֶ֙יךָ֙ לְפָנֶ֔יךָ וְהָיָ֥ה מַחֲנֶ֖יךָ קָד֑וֹשׁ וְלֹֽא־יִרְאֶ֤ה בְךָ֙ עֶרְוַ֣ת דָּבָ֔ר וְשָׁ֖ב מֵאַחֲרֶֽיךָ׃ (ס)
For the LORD thy God walketh in the midst of thy camp, to deliver thee, and to give up thine enemies before thee; therefore shall thy camp be holy; that He see no unseemly thing in thee, and turn away from thee.
Rashi on Deuteronomy
ולא יראה בך THAT HE SEE NOT IN THEE — that the Holy One, blessed be He see not in thee ערות דבר A NAKEDNESS OF ANYTHING.
Sforno on Deuteronomy
והיה מחניך קדוש, both free of ritual impurities as well as from repulsive things, even though not ritually impure.
Rashbam on Deuteronomy
מתהלך, for also the Holy Ark containing a copy of the Torah went out to war with the army, as is written: וכלי הקודש וחצוצרות התרועה בידו, ”with the holy vessels and the trumpets in his hand (Numbers 31,6) [Pinchas accompanying the 12.000 men on the punitive expedition against Midian. Ed.]