וַאֲנַ֖חְנוּ עֹשִׂ֣ים בַּמְּלָאכָ֑ה וְחֶצְיָ֗ם מַחֲזִיקִים֙ בָּֽרְמָחִ֔ים מֵעֲל֣וֹת הַשַּׁ֔חַר עַ֖ד צֵ֥את הַכּוֹכָבִֽים׃
So we wrought in the work; and half of them held the spears from the rising of the morning till the stars appeared.
Read midrashic interpretation of Nehemiah 4:15: and classical rabbinic exegesis.