If he designates her for his son is the second possible situation involving “a female slave” (Good News Translation; see verses 7-8). Good News Translation replaces the pronouns he and her with the nouns to which they refer in verse 7. Designates is the same word used in verse 8, so New International Version has “If he selects her for his son,” and Contemporary English Version has “If he selects her as a wife for his son.” This means, as Translator’s Old Testament puts it, that “he intends to make her his son’s concubine.”

He shall deal with her as with a daughter is literally “according to justice of the daughters he will do to her.” The word for “justice” is mishpat, one of several Hebrew words for “law” discussed in the introduction to 20.22-26. Here it means that which is legally determined, so the text implies that there were accepted standards by which a father was to treat his daughter. New Jerusalem Bible has “he must treat her as custom requires daughters to be treated,” and Revised English Bible has “he must allow her the rights of a daughter.” The word for daughter sometimes refers to a young woman in general, so New Jewish Publication Society’s Tanakh has “he shall deal with her as is the practice with free maidens.” But most translations favor the interpretation of daughter here, and translators are urged to do the same.

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .