Kommentar zu Bereschit 31:50

בנתי....בנתי The word is written twice, referring once to Leah and Rachel and the second time to the handmaids, because Bilhah and Zilpah were also his daughters from a concubine (Genesis Rabbah 74:13).

ראה אלוקים עד, look that G’d will punish you if you do not treat my daughters properly, seeing He is a witness The whole line may be understood as analogous to Leviticus 5,21, ומעלה מעל בה', where the trespass against G’d is considered as something that only G’d is aware of, there being no human witnesses at hand to testify against the sinner. G’d is always the third party when two people have a disagreement, seeing He knows the true facts of the situation.

אם תענה את בנותי, if you will deprive them of any of their needs, the ones stipulated as the obligation of a husband towards his wives, or even if you do not treat them with the respect due to them. According to our sages in Yuma 77 the words אם תענה refer to denial of marital relations, whereas the words אם תקח, refer to Yaaov marrying additional wives, competitors to the existing ones.