Or HaChaim on Genesis 30:15/אור החיים על בראשית ל׳:ט״ו

1 המעט קחתך את אישי, "Is it not enough that you have taken my husband, etc.?" Leah's words must be understood according to those rabbis who hold that Jacob's bed was permanently in Rachel's tent. She therefore argued that whatever time Jacob spent with Rachel in excess of a fair division was at her expense. When she used the expression ולקחת, "you have taken," she meant that the chances of bearing children were directly related to the frequency with which husband and wife engage in marital relations, as our sages state on several occasions (compare Chulin 11 et al in an indirect proof). The incident with the jasmin is related here as it is considered an aphrodisiac and its fragrance facilitates conception (Zohar 1,157). Leah complained that Rachel wanted the jasmin of her son in addition to almost monopolising Jacob's nights.

2The reason that Jacob did not divide his time equally between his two wives was simply that he had no obligation to sleep with Leah except when the latter had ritually purified herself after her menstruation (based on Exodus 21,10). After all he had not married her on his own initiative, as distinct from Rachel whom he had wanted to wed in the first place.

3לכן ישכב עמך הלילה, "therefore he shall sleep with you tonight." It appears as if this depended exclusively on Rachel's wishes. Therefore she added: "in exchange for the jasmin of your son."

4Alternatively, this can be understood as an oath. There are matters which are acquired only by means of an oath, such as items that are intangible. (the fragrance of the jasmin). Compare my commentary on Genesis 25,33 when Esau sold his birthright.