But to avoid fornication He now commands, that those who are liable to the vice of incontinency should have recourse to the remedy. For though it may seem that the statement is universal, it ought, nevertheless, to be restricted to those who feel themselves urged by necessity. As to this, every one must judge for himself. Whatever difficulty, therefore, is perceived to be in marriage, let all that cannot resist the promptings of their flesh, know that this commandment has been enjoined upon them by the Lord. But it is asked -- "Is this the only reason for entering into matrimony, that we may cure incontinency?" I answer, that this is not Paul's meaning; for as for those that have the gift of abstinence from marriage, he leaves them at liberty, [1] while he commands others to provide against their infirmity by marrying. The sum is this -- that the question is not as to the reasons for which marriage has been instituted, but as to the persons for whom it is necessary. For if we look to the first institution, it could not be a remedy for a disease which had as yet no existence, but was appointed for begetting offspring; but after the fall, this second purpose was added. This passage is also opposed to (tolugamia) polygamy For the Apostle desires that every woman have her own husband, intimating that the obligation is mutual. The man, therefore, who has once pledged his fidelity to a woman as his wife, must not separate from her, as is manifestly done in case of a second connection.

Footnotes

1 - "Il laisse la liberte de se marier ou ne se marier point;" -- "He gives liberty to marry or not marry."

Nevertheless - But (δὲ de). Though this is to be admitted as proper where it can be done, when a man has entire control of himself and his passions, and though in present circumstances it would be expedient, yet it may be proper also to enter into the marriage connection.
To avoid fornication - Greek On account of διὰ dia fornication. The word fornication is used here in the large sense of licentiousness in general. For the sake of the purity of society, and to avoid the evils of sensual indulgence, and the corruptions and crimes which attend an illicit contact, it is proper that the married state should be entered. To this vice they were particularly exposed in Corinth. See the introduction. Paul would keep the church from scandal. How much evil, how much deep pollution, how many abominable crimes would have been avoided, which have since grown out of the monastic system, and the celibacy of the clergy among the papists, if Paul's advice had been followed by all professed Christians! Paul says that marriage is honorable, and that the relations of domestic life should be formed to avoid the evils which would otherwise result. The world is the witness of the evils which flow from the neglect of his advice. Every community where the marriage tie has been lax and feeble, or where it has been disregarded or dishonored, has been full of pollution, and it will always be. Society is pure and virtuous, just as marriage is deemed honorable, and as its vows are adhered to and preserved.
Let every man - Let the marriage vow be honored by all.
Have his own wife - And one wife to whom he shall be faithful. Polygamy is unlawful under the gospel; and divorce is unlawful. Let every man and woman, therefore, honor the institution of God, and avoid the evils of illicit indulgence.

To avoid fornication - Δια τας πορνειας· verto, propter exercendam libidinem, vel ut libidinem licite exercere liceat. Probo hanc notionem ex Hebraeo, ibi זנה, zanah, est libidinem exercere, Hosea 4:10 : For they shall eat and not have enough; they shall commit whoredom, תזנו, libidinem exercebunt, and shall not increase. Here the prophet certainly does not speak of whoredom in our sense of the word; for the persons he mentions expected to have children, which cannot be said of those who are addicted to improper connections: the prophet speaks concerning married persons, whom he threatens with a privation of children, notwithstanding libidinem exercebant in order to have numerous families. See Schoettgen. The following verse shows that this is the apostle's meaning.
Let every man have his own wife - Let every man have one woman, his own; and every woman one man, her own. Here, plurality of wives and husbands is most strictly forbidden; and they are commanded to marry for the purpose of procreating children.
In the Jewish constitutions there are some things not only curious, but useful, respecting marriage. "There are four causes which induce men to marry:
1. Impure desire;
2. To get riches;
3. To become honorable;
4. For the glory of God.
Those who marry through the first motive beget wicked and rebellious children. Those who marry for the sake of riches have the curse of leaving them to others. Those who marry for the sake of aggrandizing their family, their families shall be diminished. Those who marry to promote the glory of God, their children shall be holy, and by them shall the true Church be increased."

Nevertheless, to avoid fornication,.... Or "fornications"; meaning either the frequent commission of that sin; or all sorts of uncleanness and pollution, which may be avoided by wedlock, and the proper use of the marriage bed, where the gift of continency is not bestowed: wherefore to prevent unlawful copulations, as of single persons with one another, or of a married person with a single one, the apostle advises, as being what is right and proper,
let every man have his own wife, and let every woman have her own husband; that is, let every man that has a wife enjoy her, and make use of her, and let every woman that has an husband, receive him into her embraces; for these words are not to be understood of unmarried persons entering into a marriage state, for the words suppose them in such a state, but of the proper use of the marriage bed; and teach us that marriage, and the use of it, are proper remedies against fornication; and that carnal copulation of a man with a woman ought only to be of husband and wife, or of persons in a married state; and that all other copulations are sinful; and that polygamy is unlawful; and that one man is to have but one wife, and to keep to her; and that one woman is to have but one husband, and to keep to him.

Here the general rule is given
to avoid fornication--More literally, "on account of fornications," to which as being very prevalent at Corinth, and not even counted sins among the heathen, unmarried persons might be tempted. The plural, "fornications," marks irregular lusts, as contrasted with the unity of the marriage relation [BENGEL].
let every man have--a positive command to all who have not the gift of continency, in fact to the great majority of the world (1-Corinthians 7:5). The dignity of marriage is set forth by Paul (Ephesians 5:25-32), in the fact that it signifies the mystical union between Christ and the Church.

Yet, when it is needful, in order to avoid fornication, let every man have his own wife. His own - For Christianity allows no polygamy.