King James Version (KJV)
One man of you shall chase a thousand: for the LORD your God, he {it is} that fighteth for you, as he hath promised you.
Modern English
One man of you shall chase a thousand; for it is Yahweh your God who fights for you, as he spoke to you.
Hebrew
אִישׁ־אֶחָ֥ד מִכֶּ֖ם יִרְדָּף־אָ֑לֶף כִּ֣י ׀ יְהוָ֣ה אֱלֹהֵיכֶ֗ם ה֚וּא הַנִּלְחָ֣ם לָכֶ֔ם כַּאֲשֶׁ֖ר דִּבֶּ֥ר לָכֶֽם׃
ʾiysh-ʾeḥad mikem yirdaf-ʾalef kiy ׀ yhvah ʾeloheykem hvʾ hanilḥam lakem kaʾasher diber lakem