1 Corinthians 7:2

Nevertheless, to avoid fornication Literally, on account of the fornications, i.e. the habitual practice of this vice in the Church of Corinth. See note on ch. 1 Corinthians 6:13. We are not to suppose (see Meyer) that we have the whole of the Apostle's view of marriage, but simply that which connects itself with the question that has been asked him. To understand the doctrine of marriage, as generally delivered in the Christian Scriptures, we must compare St John 2; Ephesians 5:23-30; 1 Timothy 5:14; Hebrews 13:4; 1 Peter 3:1-7. "These are questions of casuistry, which depend upon the particular case, from which word the term casuistry is derived." Robertson.

let every man have his own wife, and let every woman have her own husband Calvin remarks that we have here a prohibition of polygamy.