Read 1 Corinthians 5:1 Using Other Translations
It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father's wife.
It is actually reported that there is sexual immorality among you, and of a kind that is not tolerated even among pagans, for a man has his father's wife.
I can hardly believe the report about the sexual immorality going on among you—something that even pagans don’t do. I am told that a man in your church is living in sin with his stepmother.