כִּֽי־נָשְׂא֣וּ מִבְּנֹֽתֵיהֶ֗ם לָהֶם֙ וְלִבְנֵיהֶ֔ם וְהִתְעָֽרְבוּ֙ זֶ֣רַע הַקֹּ֔דֶשׁ בְּעַמֵּ֖י הָאֲרָצ֑וֹת וְיַ֧ד הַשָּׂרִ֣ים וְהַסְּגָנִ֗ים הָֽיְתָ֛ה בַּמַּ֥עַל הַזֶּ֖ה רִאשׁוֹנָֽה׃ (ס)
For they have taken of their daughters for themselves and for their sons; so that the holy seed have mingled themselves with the peoples of the lands; yea, the hand of the princes and rulers hath been first in this faithlessness.’
Read halakhic rulings (Jewish law) on Ezra 9:2: and classical halakhic sources.