Exodus 21:9

Betrothed her unto his son, he shall deal with her - He shall give her the same dowry he would give to one of his own daughters. From these laws we learn, that if a man's son married his servant, by his father's consent, the father was obliged to treat her in every respect as a daughter; and if the son married another woman, as it appears he might do, Exodus 21:10 , he was obliged to make no abatement in the privileges of the first wife, either in her food, raiment, or duty of marriage. The word ענתה onathah , here, is the same with St. Paul's οφειλομενην ευνοιαν , the marriage debt, and with the ὁμιλιαν of the Septuagint, which signifies the cohabitation of man and wife.