וַיְקַנֵּ֥א יְהוָ֖ה לְאַרְצ֑וֹ וַיַּחְמֹ֖ל עַל־עַמּֽוֹ׃
און גאָט האָט זיך אָנגענומען פֿאַר זײַן לאַנד, און האָט זיך דערבאַרימט אױף זײַן פֿאָלק.
Mishneh Torah, Woman Suspected of Infidelity
The warning that is mentioned in the Torah - "And he warned his wife" - is that he tells her in the presence of witnesses, "Do not seclude yourself with Mr. so-and-so," even if that man is her father, her brother, a gentile, a slave, or an impotent person who cannot achieve an erection or produce children."