1Cor 7:12

“The Lord also showed that certain precepts were enacted for them by Moses, on account of their hardness [of heart], and because of their unwillingness to be obedient, when, on their saying to Him, "Why then did Moses command to give a writing of divorcement, and to send away a wife?" He said to them, "Because of the hardness of your hearts he permitted these things to you; but from the beginning it was not so;" thus exculpating Moses as a faithful servant, but acknowledging one God, who from the beginning made male and female, and reproving them as hard-hearted and disobedient. And therefore it was that they received from Moses this law of divorcement, adapted to their hard nature. But why say I these things concerning the Old Testament? For in the New also are the apostles found doing this very thing, on the ground which has been mentioned, Paul plainly declaring, "But these things I say, not the Lord." And again: "But this I speak by permission, not by commandment." And again: "Now, as concerning virgins, I have no commandment from the Lord; yet I give my judgment, as one that hath obtained mercy of the Lord to be faithful." But further, in another place he says: "That Satan tempt you not for your incontinence." If, therefore, even in the New Testament, the apostles are found granting certain precepts in consideration of human infirmity, because of the incontinence of some, lest such persons, having grown obdurate, and despairing altogether of their salvation, should become apostates from God,-it ought not to be wondered at, if also in the Old Testament the same God permitted similar indulgences for the benefit of His people, drawing them on by means of the ordinances already mentioned, so that they might obtain the gift of salvation through them, while they obeyed the Decalogue, and being restrained by Him, should not revert to idolatry, nor apostatize from God, but learn to love Him with the whole heart.”

“Therefore, when in these days a certain woman removed her marriage from the pale of the Church, and united herself to a Gentile, and when I remembered that this had in days gone by been done by others: wondering at either their own waywardness or else the double-dealing of their advisers, in that there is no scripture which holds forth a licence of this deed,-"I wonder," said I, "whether they flatter themselves on the ground of that passage of the first (Epistle) to the Corinthians, where it is written: If any of the brethren has an unbelieving wife, and she consents to the matrimony, let him not dismiss her; similarly, let not a believing woman, married to an unbeliever, if she finds her husband agreeable (to their continued union), dismiss him: for the unbelieving husband is sanctified by the believing wife, and the unbelieving wife by the believing husband; else were your children unclean." It may be that, by understanding generally this monition regarding married believers, they think that licence is granted (thereby) to marry even unbelievers.”

“For as when discoursing about separating from fornicators, he made the matter easy by the correction which he applied to his words, saying, "Howbeit, not altogether with the fornicators of this world;" so also in this case he provideth for the abundant easiness of the duty, saying, "If any wife have a husband, or husband a wife, that believeth not, let him not leave her." What sayest thou? "If he be an unbeliever, let him remain with the wife, but not if he be a fornicator? And yet fornication is a less sin than unbelief." I grant, fornication is a less sin: but God spares thine infirmities extremely. And this is What He doth about the sacrifice, saying, "Leave the sacrifice, and be reconciled to thy brother." This also in the case of the man who owed ten thousand talents. For him too He did not punish for owing him ten thousand talents, but for demanding back a hundred pence from his fellow-servant He took vengeance on him.”

“But to the rest speak I, not the Lord,.... He had spoken before to married persons in general, and had delivered not his own sentiments barely, but the commandment of the Lord, that such should never separate from, or put away each other; in which he has respect to such as were upon equal foot in matters of religion, who were both of them believers in Christ; but now he speaks to the rest, to such as were unequally yoked, the one a believer, the other an unbeliever; and what he delivers on this head, concerning their living together, there being no express determination of this matter by the Lord himself, he under divine inspiration gives his sense of it; as that such marriages were valid, and that such persons ought to live together, and not separate on account of difference in religion: or the sense is, that as "to the rest" of the things they had wrote to him about, besides what he had given answer to already, he should speak to under divine illumination; though he had not an express law of Christ to point unto them, as the rule of their conduct: and particularly, whereas they had desired his judgment and advice upon this head, whether one who before conversion had married an unbeliever, ought to live with such an one, or whether it would not be advisable to leave, or put such away, to it he answers, if any brother hath a wife that believeth not; that is, if any man who is now a brother, one called by the grace of God, and is in church fellowship, has a wife to whom he was married whilst in a state of unregeneracy and infidelity; who is as she was when he married her, entirely destitute of faith in Christ; not one that is weak in the faith, or only makes an outward profession, but that has no faith at all in Christ, nor in his Gospel, not so much as an historical one; who disbelieves, denies, and rejects, the truths of the Gospel: and she be pleased to dwell with him; loves her husband, chooses to continue with him, notwithstanding their different sentiments of religion: let him not put her away; infidelity is no reason for a divorce. The Gospel revelation does not dissolve the natural obligations men and women are in to one another. The Jews had a law prohibiting marriages with Heathens and idolaters; and such marriages were dissolved, and such wives put away, Exo 34:16 but this was a law peculiar to that people, and was not obligatory on other nations, and especially has no place under the Gospel dispensation.”

“But to the rest speak I, not the Lord - As if he had said: For what I have already spoken I have the testimony of the Lord by Moses, and of my own Lord and Master, Christ; but for the directions which I am now about to give there is no written testimony, and I deliver them now for the first time. These words do not intimate that the apostle was not now under the influences of the Divine Spirit; but, that there was nothing in the sacred writings which bore directly on this point. If any brother - A Christian man, have a wife that believeth not, i.e. who is a heathen, not yet converted to the Christian faith, and she be pleased to dwell with him, notwithstanding his turning Christian since their marriage, let him not put her away because she still continues in her heathen superstition.”

“For to the rest, &c. This was a case entirely new, which the wisdom of the apostle regulates according to the laws of charity. Tertullian thinks that some of the faithful, who had been converted from paganism, did not esteem it lawful to live any longer with their wives, who were yet buried in the superstitions of idolatry, which scruples St. Paul answers, guided as he was, by the particular lights of the Holy Ghost. (Calmet) — Not the Lord. That is, it is the command of the Lord, for such even as are separated, not to marry to another, but when I advised the unmarried not to marry, this is a counsel, or advice, not a divine precept, which doctrine he repeats again before the end of this chapter, ver. 25, 28, and 39. — If any brother have a wife that believeth not, &c. St. Paul speaks of two that were joined by a contract of marriage, when both of them were infidels, and that one of them is converted to the Christian faith: we do not read of any precept that Christ gave, as to those marriages, but the apostle seems to order by his apostolical authority, that they continue as man and wife, unless the party that remains still an infidel, will needs depart; then, says the apostle, let such an one depart. There is also another case, to wit, when the man or woman remaining an infidel, will not live without continual injuries and blasphemies against God and the Catholic religion, so that there can be no peace on that account betwixt them. In these two cases, according to the canons of the Church, it is looked upon as no marriage, so that the party converted may marry another. And this seems grounded on the reason, which the apostle here gave, that God hath called us in peace. (Witham)”

“to the rest--the other classes (besides "the married," Co1 7:10, where both husband and wife are believers) about whom the Corinthians had inquired, namely, those involved in mixed marriages with unbelievers. not the Lord--by any direct command spoken by Him. she be pleased--Greek, "consents": implying his wish in the first instance, with which hers concurs.”