But if an unbeliever depart. This is the second department of his statement, in which he sets at liberty a believing husband, who is prepared to dwell with an unbelieving wife, but is rejected by her, and in like manner a woman who is, without any fault on her part, repudiated by her husband; for in that case the unbelieving party makes a divorce with God rather than with his or her partner. There is, therefore, in this case a special reason, inasmuch as the first and chief bond is not merely loosed, but even utterly broken through. While some are of opinion that we are at this day situated in a much similar way with Papists, [1] we ought to consider wisely what difference there is between the two cases, that we may not attempt anything rashly. In peace. Here, too, interpreters differ; for some take it in this way -- "We are called in peace: let us therefore avoid all ground and occasion of quarrels." I take it in a more simple way: "Let us, so far as we can, cultivate peace with all, to which we have been called. We must not, therefore, rashly separate from unbelievers, unless they first make a divorce. God, therefore, has called us in peace to this end, that we might cultivate peace with all, by acting properly towards every one." This, then, belongs to the former department of his statement -- that believers ought to remain with unbelievers, if they are pleased, etc., (1-Corinthians 7:12 and 13,) because a desire for divorce is at variance with our profession.

Footnotes

1 - "Que nous auons auiourd'huy semblable cause de nous departir d'avec les Papistes;" -- "That we have at this day similar ground of separation from Papists."

But if the unbelieving depart - If they choose to leave you.
Let him depart - You cannot prevent it, and you are to submit to it patiently, and bear it as a Christian.
A brother or a sister is not under bondage - Many have supposed that this means that they would be at liberty to marry again when the unbelieving wife or husband had gone away; as Calvin, Grotius, Rosenmuller, etc. But this is contrary to the strain of the argument of the apostle. The sense of the expression "is not bound," etc. is, that if they forcibly depart, the one that is left is not bound by the marriage tie to make provision for the one that departed; to do acts that might be prejudicial to religion by a violent effort to compel the departing husband or wife to live with the one that is forsaken; but is at liberty to live separate, and should regard it as proper so to do.
God hath called us to peace - Religion is peaceful. It would prevent contentions and broils. This is to be a grand principle. If it cannot be obtained by living together, there should be a peaceful separation; and "where" such a separation has taken place, the one which has departed should be suffered to remain separate in peace. God has called us to live in peace with all if we can. This is the general principle of religion on which we are always to act. In our relation to our partners in life, as well as in all other relations and circumstances, this is to guide us. Calvin supposes that this declaration pertains to the former part of this verse; and that Paul means to say, that if the unbelieving depart, he is to be suffered to do so peaceably rather than to have contention and strife, for God has called us to a life of peace.

But if the unbelieving, depart - Whether husband or wife: if such obstinately depart and utterly refuse all cohabitation, a brother or a sister - a Christian man or woman, is not under bondage to any particular laws, so as to be prevented from remarrying. Such, probably, the law stood then; but it is not so now; for the marriage can only be dissolved by death, or by the ecclesiastical court. Even fornication or adultery does not dissolve the marriage contract; nor will the obstinate separation of any of the parties, however long continued, give the party abandoned authority to remarry. If the person have been beyond sea, and not heard of for seven years, it is presumed he may be dead; and marriage has been connived at in such cases. If there be no person to complain, it may be presumed that there is none injured. But I have known instances where even a marriage after seven years' absence has been very unfortunate; the husband returning at the end of ten or twelve years, and to his utter distress finding his wife married to another man, and with issue of that marriage! There can be no safety in this case, unless there be absolute certainty of the death of the party in question.
God hath called us to peace - The refractory and disagreeing party should not be compelled to fulfill such matrimonial engagements as would produce continual jarring and discord. At the same time each should take care that he give no cause for disagreements and separations, for the author of the Christian religion is the author of peace, and has called us to it.

(10) But if the unbelieving depart, let him depart. A brother or a sister is not under bondage in (m) such [cases]: (11) but God hath called us to peace.
(10) He answers a question: what if the unfaithful forsake the faithful? Then the faithful is free, he says, because he is forsaken by the unfaithful.
(m) When any such thing happens.
(11) Lest any man upon pretence of this liberty should give an occasion to the unfaithful to depart, he shows that marriage contracted with an infidel ought to be kept peaceably, that if it is possible the infidel may be won to the faith.

But if the unbelieving depart,.... If the unbelieving party, man or woman, separate themselves from the believing party on account of religion, and in hatred to it, and will not live with the believer unless Christ is denied, his Gospel abjured, and his ordinances and worship relinquished:
let him depart; he or she, though not without making use of all proper means to retain them; but if, after all, they will go, unless such things are complied with as are unreasonable and sinful, they are not to be held, but let go; and the deserted person may sit down contented, being not to be blamed, the fault entirely lying upon the deserter:
a brother or a sister is not under bondage in such cases. The Ethiopic version reads it, "to such an one"; one that is called by grace a church member, and so a brother or sister in Christ, is not to be subject to an unbeliever in matters of conscience, in things appertaining to the worship of God, and the service and glory of Christ; nor, being in such circumstances, that either Christ must be forsaken, or the unbeliever will depart, are they obliged to yield to such an one, but rather suffer a departure; nor are they bound to remain unmarried, but are free to marry another person, after all proper methods have been tried for a reconciliation, and that appears to be impracticable; desertion in such a case, and attended with such circumstances, is a breach of the marriage contract, and a dissolution of the bond, and the deserted person may lawfully marry again; otherwise a brother, or a sister in such a case, would be in subjection and bondage to such a person:
but God hath called us to peace; which ought to be sought after and maintained, so far as it can be consistent with truth, the glory of God, the honour of Christ, and interest of religion. The believing party being threatened with a desertion, ought as much as possible to seek for peace and reconciliation, and do all that can be to prevent a departure; for saints are called by the grace of God, to follow after and cultivate peace, not only with one another in their Christian communion as saints, but with all men, even their enemies, and especially with such as are so nearly allied; wherefore the departure should not be easily admitted, or a new marriage be suddenly entered into, reconciliation, if it can be obtained, being most eligible and becoming a Christian.

if . . . depart--that is, wishes for separation. Translate, "separateth himself": offended with her Christianity, and refusing to live with her unless she renounce it.
brother or a sister is not under bondage--is not bound to renounce the faith for the sake of retaining her unbelieving husband [HAMMOND]. So Deuteronomy 13:6; Matthew 10:35-37; Luke 14:26. The believer does not lie under the same obligation in the case of a union with an unbeliever, as in the case of one with a believer. In the former case he is not bound not to separate, if the unbeliever separate or "depart," in the latter nothing but "fornication" justifies separation [PHOTIUS in Æcumenius].
but God hath called us to peace--Our Christian calling is one that tends to "peace" (Romans 12:18), not quarrelling; therefore the believer should not ordinarily depart from the unbelieving consort (1-Corinthians 7:12-14), on the one hand; and on the other, in the exceptional case of the unbeliever desiring to depart, the believer is not bound to force the other party to stay in a state of continual discord (Matthew 5:32). Better still it would be not to enter into such unequal alliances at all (1-Corinthians 7:40; 2-Corinthians 6:14).

A brother or a sister - A Christian man or woman. Is not enslaved - is at full liberty. In such cases: but God hath called us to peace - To live peaceably with them, if it be possible.