Jeremiah 34:11 Midrash

וַיָּשׁ֙וּבוּ֙ אַחֲרֵי־כֵ֔ן וַיָּשִׁ֗בוּ אֶת־הָֽעֲבָדִים֙ וְאֶת־הַשְּׁפָח֔וֹת אֲשֶׁ֥ר שִׁלְּח֖וּ חָפְשִׁ֑ים ויכבישום [וַֽיִּכְבְּשׁ֔וּם] לַעֲבָדִ֖ים וְלִשְׁפָחֽוֹת׃ (ס)

but afterwards they turned, and caused the servants and the handmaids, whom they had let go free, to return, and brought them into subjection for servants and for handmaids;