It is reported commonly. — Better, There is absolutely said to be fornication among you, and such fornication as is not even among the Gentiles. All the best MSS. omit the word “named.” The force of the statement is that the fornication was of such a kind (with a stepmother) as even the Gentile world, immoral as it was, regarded with disgust, and how infinitely worse, then, was it to find such tolerated amongst Christians, whose moral standard ought to be much higher.
One should have his father’s wife. — The word “have” here used always implies in the New Testament actual marriage. It is, therefore, probable that she had been divorced from his father. The word for “his father’s wife” is the Hebrew form of expression for stepmother. St. Chrysostom suggests “he said not his ‘stepmother,’ but ‘his father’s wife,’ so as to strike much more severely;” but probably St. Paul used the Hebrew phrase instead of the ordinary Greek word for “stepmother,” as it was in this phraseology that such a union was forbidden by the law of Moses (Leviticus 18:8).