וַאֲשֶׁ֛ר לֹא־נִתֵּ֥ן בְּנֹתֵ֖ינוּ לְעַמֵּ֣י הָאָ֑רֶץ וְאֶת־בְּנֹ֣תֵיהֶ֔ם לֹ֥א נִקַּ֖ח לְבָנֵֽינוּ׃
and that we would not give our daughters unto the peoples of the land, nor take their daughters for our sons;
Read midrashic interpretation of Nehemiah 10:31: and classical rabbinic exegesis.