Commentary for Genesis 39:10

לשכב אצלה TO LIE BY HER — even without sinning (Genesis Rabbah 87:6).

TO LIE ‘ETZLA’ (BY HER). The meaning of this expression is as Rabbi Abraham ibn Ezra interpreted it: “even to lie near her, each in their garment, or to be with her for general conversation.” This interpretation is correct since we do not find the word etzla (near her) in Scripture in connection with sexual intercourse, only the word ima (with her) or othah (with her), as for example: Lie ‘imi’ (with me);²²⁸Verse 12 here. And if any man lie ‘othah’ (with her);²²⁹Leviticus 15:24. And the women ravished (‘tishachavnah’).²³⁰Zechariah 14:2. In tishachavnah, the plural form of othah is implicit.

להיות עמה, Joseph was even careful not to find himself alone with Potiphar’s wife until there came a day when he was forced to be alone with her in the house as all the other members of the household were occupied outside the house. According to Bereshit Rabbah 87,7 all the other people on that day had gone to watch the river Nile flood its banks, an annual event.