v.12 In the previous verses we considered last Lord’s Day, Christians are forbidden to divorce. Paul doesn’t raise the exception that we find in Jesus’ teaching, that of adultery, he is speaking generally. Now Paul moves to another situation, not an uncommon one in that time and place: a Christian married to an unbeliever. Many of those who became Christians in those days were, of course, married people. And it was not always the case, just as it is not always the case today, that the husband and the wife became Christians together. If a Christian is forbidden to marry a non-Christian and is warned against the consequences of being “unequally yoked,” as Paul puts it in another place, it is not hard to understand that new Christians who now found themselves married to unbelievers, not by their own fault but as a result of the grace of God given to them but not to their spouses, would wonder what they were supposed to do. Almost certainly there were those in the Corinthian church who were arguing that, just as sexual relations contaminate a marriage, the issue Paul dealt with first in this chapter, so an unbelieving spouse contaminates a marriage. [Fee, 298]
By the way, when Paul says, “I, not the Lord” he means only that he has no specific commandment from Jesus to point them to. The Lord himself never addressed this particular question in his teaching. What Paul the Apostle says is no less authoritative, of course, for he speaks for God, and he is trustworthy, as he says in v. 25, for he has the Spirit of God, as he says in v. 40.
v.13 In other words, in these cases, the initiative in seeking a divorce lies with the unbelieving spouse.
v.14 Paul uses strong language here. The unbelieving husband has been made holy through his wife and the children of the marriage have been made holy by the presence of the one Christian spouse. We would say, in our theological tradition, the presence of the believing spouse causes the children to lie within the covenant and not outside of it. Taking the whole of the Bible’s teaching together, and Paul’s repetition of this thought in a different way in v. 16, we should say the hope and expectation of the salvation of the children in such a family should be stronger than the hope and expectation of the unsaved spouse. There are direct promises in the Bible, frequently repeated, concerning the children; no promises as such regarding the unsaved spouse. But, it is not unlike God to save the unsaved spouse, much as he loves his people, much as he loves marriage and family, and we know that throughout history he has very often done so.
v.15 The controversy here is whether “is not bound” means simply “is not bound to the marriage” or means also “is free to remarry.” It seems clear to me that the main point here is that the believer is not bound to the marriage. He should let the unbelieving spouse depart. But, the inference of the phrase “is not bound” is also clearly that the marriage being ended through no fault of the Christian, he or she is free to remarry. The similar language used of the widow in v. 39 strongly confirms this inference.
“God has called us to live in peace” thus means either that the Christian spouse should maintain the marriage peaceably if the unbelieving spouse is willing or that, should he or she wish to depart, the Christian should not have a bad conscience about it. [Thiselton, 538]
v.16 The NIV omits the “For” with which the sentence begins. The question here is whether to read the questions optimistically or pessimistically. In the latter case, reading them pessimistically as does the NIV, the letting go of the departing spouse is supported by this consideration: how, after all, can you know if you will ever see your spouse a Christian. That is, it may very well not happen, and so let him or her go. If read optimistically, the words mean: stick with the marriage if the unbeliever is willing to remain, perhaps you will be the instrument of bringing salvation to your husband or wife. An optimistic reading is strongly supported by the similar argument in 1 Peter 3 where wives are encouraged to live godly lives before their husbands in order that the husbands may be won to salvation by the testimony of their wives.
As you know, this text has become the eye of a storm over the last generation as divorce rates have skyrocketed in the culture at large and in the evangelical church. Christians today want to know if they can leave a marriage and they want to know if, having left it, they can remarry. And Christian ministers and teachers and writers have weighed in with contradictory answers to those questions.
But what we are given here is a typical slice of the Bible’s ethical teaching. In the Bible we are given fundamental principles, such as that expressed in Genesis 2: “a man shall leave his father and mother and be united to his wife and they will become one flesh.” That is, the fundamental position of Holy Scripture is that marriage is the profound union of a man and a woman and God intends for it to create a family and to be permanent. Then, along the way, are added some few instances of case law. The law of Moses dealt briefly with divorce and remarriage in Deuteronomy 24. Jesus forbade divorce except for adultery in Matthew 5 and 19. And now Paul takes up the case of spiritually mixed marriages here in 1 Cor. 7, permitting the Christian spouse to let go of a marriage to an unbeliever who does not wish to be married to a Christian. There are a few other instances in which these issues are raised in one way or another. There is very little more in all of the Bible to direct us in this matter of divorce and remarriage. No wonder the controversy!
But, as I said, this is the way the Bible teaches its ethics in respect to all areas of conduct. We are given large principles, a few instances of case law – that is, the application of those large principles to specific ethical cases and questions – and then we are left, and the elders of the church are left, to apply that material to other situations, different cases, other questions, and come to a proper decision about what is right and what is wrong. Whether we are talking about what should or should not be done on the Sabbath day, or whether or when we may speak what is untrue, or how far does the obligation to care for our neighbor extend, we are always left to apply general principles and to learn the art of this application by comparing the few cases in the Scripture where those principles were applied to specific questions of conduct.
Paul deals here with an unbelieving spouse who either is happy to stay in a marriage with a Christian or is unwilling to stay and picks up and leaves. But there are a thousand other situations that are not addressed specifically in the Bible and to which this single piece of case law must be applied in one way or another.
What about a situation in which a Christian woman is married to an unsympathetic unbelieving husband who practices another religion and demands his wife to participate with him? In other parts of the world this is often a pressing question. What of a man who persecutes his wife because of her Christian convictions? Calvin and the elders in Geneva had to deal with such cases in the days of the Reformation, when Catholic husbands refused to tolerate the evangelical convictions of their newly-converted wives. What of a husband who beats his wife? I served some years ago on a study committee for the General Assembly of the Presbyterian Church in America which was given the assignment of answering that very question: could physical abuse be considered the equivalent of actual desertion? Could we say to a Christian woman who was being beaten by her husband: he has, for all intents and purposes, left you and you are free to let him go? What of a young woman who has a stroke which is thought to have been, at least in part, precipitated by a husband’s cruel and angry treatment of her? Sound farfetched? We faced that very question some years ago in this church. The possible scenarios go on and on. What of a husband who contracts Elephantiasis, a disease that intensifies sexual craving but, at the same time, renders a man contagious? What is a wife’s duty then? Do you think I am pulling your leg? Calvin and the elders of the church in Geneva had to deal with that case also. What about a woman who does not desert the marriage in the sense of leaving, but refuses to fulfill the obligations of a wife and, against all counsel, remains determined in her refusal?
And, perhaps, more common a consideration: what is to be done when the spouse that leaves is a professing Christian and continues to make his or her profession of faith even after leaving the marriage. What would Paul say about that? What would he tell the deserted spouse in such a case? I know of many cases in which the desertion of a marriage has led to church discipline and even excommunication so that the deserting spouse is finally not regarded as a Christian at all and 1 Corinthians 7:15 is applied to the case. But, I also know of cases where that is not so and the deserting spouse is not disciplined and remains a member in good standing of the church. How does 1 Cor. 7:12-16 apply in that case?
These are the questions that are being faced by church elders and by Christian consciences all the time nowadays. There is no other way to find the answer, to come to a conclusion than in the time-honored biblical way of taking the Bible’s general principles of conduct and using the few instances of case law to learn the art of application to new situations and new circumstances. It is an art and that is why Christians do not always agree with one another as to what is permitted and what is forbidden. Even Christians in our own Presbyterian Church in America, who agree about the inerrancy of the Bible, who accept the Westminster Confession of Faith as a faithful summary of the Bible’s teaching, do not agree in specific instances as to what the Bible requires and what it forbids in respect to divorce and remarriage. In our church, thankfully, there is a general agreement, but when it comes to cases, opinions differ. This is one very important reason why the church’s elders must be wise, discerning men who are skilled at bringing the Bible to bear on the issues of life. These are not easy questions to answer and, yet, anyone can see that they bear mightily on the spiritual wellbeing of God’s people.
I don’t mean to suggest to you that you cannot know what is right in a specific case. Holy Scripture, Paul tells us, thoroughly equips us for every good work. I am saying only that the business of applying the whole of Scripture to specific ethical questions can be a demanding and difficult one.
But, it is always made easier, much easier, by one thing. And that is a true desire, a genuine commitment of the heart to seek and to do God’s will. We are all well aware of the fact that we are tempted to want to do God’s will only to the extent that it coincides with our own. We can kid ourselves into thinking that what we want is God’s will when, in fact, we are determined to do what we please. Time and again we have heard Christian people tell us that it was God’s will that they do this or that, or that God told them to do this or that, or directed them in this way or that. And is it not almost invariably the case that what they took to be the will of God neatly coincided with what we might well have expected them to want to do themselves. How many times, after all, have we heard someone say, “It is God’s will that I give all my money to the poor,” or, “It is God’s will that I give up this really good job and take a much less well paid one because it affords fewer temptations to sin.” I remember Harry DeSoto mentioning to me years ago, that even when he was a boy, he had already observed that, apparently, it was always God’s will for a minister to go to a larger, better-paying church.
And, what about this text before us? How many Christians today are cheerfully willing to say that it is God’s will for them to remain in an unfulfilling, sometimes punishingly difficult marriage with a man or a woman who does not share any of the convictions and commitments that are most precious to a Christian?
Think about what Paul is actually saying here. It was the Greco-Roman world. Imagine yourself a new Christian. Your eyes have been opened to a wonderful new reality. Your heart has been changed. God has drawn near to you. You have a completely new set of friends and a new kind of fellowship with them. You want to do new things. You have become acquainted with an entirely new way of marriage. You see in the church husbands and wives who love one another in a distinctly Christian way and serve the Lord together.
But, your husband isn’t interested in any of this. Perhaps you never had an affectionate marriage, perhaps your new-found faith has already put a strain on your relationship with your husband. He mocks and makes fun of your religious zeal, your new friends, your new practices. Perhaps it is worse than that. He discourages you from attending Christian worship. He wants you to attend his religious activities and to continue to participate in social and cultural events that you now find utterly uninteresting at best and, at worst, incompatible with your new loyalty to Jesus Christ. This is the practical effect of what Paul teaches here in 7:12-16. Christian folk stuck often in deeply unhappy, unfulfilling, difficult, frustrating marriages. That is what this means. That is the intensely practical and real-life effect of what he commands us here. Christian husbands and wives living for years in very unfulfilling marriages.
It is not always so, of course. Sometimes, in the goodness of the Lord, a Christian can be contentedly married to a non-Christian, even for many years, but there are, even then, inevitable tensions and sorrows. If the Christian spouse is devout, if he or she is faithful, living in intimate fellowship with an unbeliever cannot help but produce tension. Think about it: one of you is going to heaven and the other to hell; one of you lives by the light of the Word of God and the other is indifferent, if not hostile, to the teaching of the Bible; one of you looks at the world and your life from the vantage point of the kingdom of God and the other remains a servant of the devil; one of you cares first and foremost about pleasing God and the other doesn’t give a fig for God or serving him; one of you finds real pleasure and satisfaction in the duties and obligations of the Christian life and the other is always interested in something else. And, if there are children, one of you is conscientiously determined to bring them up for the Lord and the other, whether he intends to or not, is working at cross-purposes to you at every turn. I say, even when the husband and wife love each other deeply, as is sometimes the case in spiritually mixed marriages, it is not easy. And, as we know, many times the husband and wife do not love one another deeply and the Christian wife is left longing for things she knows will never be hers in her marriage, and the Christian husband similarly.
And here comes the Apostle Paul telling you that so long as your husband is willing to remain your husband you must remain his wife. Or you must remain her husband. And, lest we, early 21st century folk that we are, find it incomprehensible that God would ask such a thing of us, we have the same teaching repeated in 1 Peter 3.
Would God ask such a thing of one of his children? Would he ask a son or daughter of his to remain for years in an unhappy marriage? Would he ask something as difficult as that? Well, yes, he may very well. He asked terrible things of his Son and he has, through the ages, asked very difficult things of his children: that they should endure heavy sorrows for his sake, even that they should give up their lives for him.
We may not know why any particular believer should be asked to endure so much, but we do know why every believer should be willing to suffer any manner of hardship for the sake of obeying God and serving Jesus Christ: Paul will give us the reason later in this same chapter, in verse 29. The time is short. We are soon for heaven. We cannot measure our lives, we cannot determine what is to be done with them by any calculation of reward in this world. We must always have an eye on that world soon to come, the world that lasts forever, the world of endless and boundless joy. We can endure any hardship and know it right to do so, because we are sure that in due time all our sorrows will be swallowed up and everlasting joy will be upon our heads.
And God would never ask his children to endure such hardship in this life if he did not fully intend to make them forget all about their hardships when he took their hand and welcomed them into the city that has foundations. Here is where this teaching about marriage and divorce intersects with the lives of many of you who are not married or have happy Christian marriages and who have no particular need to hear about spiritually mixed marriages. It is this lesson that heaven often requires hardship here in this world. It is being required to face the fact that God, for the sake of eternal things, pronounces irreversible judgments that are punishingly difficult for his children to endure. It may be something else in your life than remaining in a difficult marriage. But, are you as willing to obey at great cost as must be the Christian spouse who is married to an unbeliever? You must be, you will be, if you have your mind set on things above, where Christ is, seated at the Right Hand of God.
So, then, here is the key. Who will get right the meaning of 1 Corinthians 7:12-16? Who will know how rightly to apply these verses and these commandments? Who will know what they permit and what they forbid in the thousand specific situations that Christians face today? Well, I will tell you. It will be that man, that woman who really wants to do the will of God. Who loves God and wants to please him. Who is so grateful to Christ that nothing matters so much to him or to her as simply giving glory to the Redeemer. Who wants to go to heaven and to go there with a clean conscience and a consistent testimony.
Who will get the interpretation of these verses right? It will be that Christian who knows full well and accepts entirely the very real possibility that loyalty to Jesus Christ in this world of sin and death, in this world, where the issue of the everlasting life of human beings is being fought out to the death, will require great sacrifice, heavy losses, the forsaking of many pleasures, and the abandonment of many earthly hopes and dreams. It will require participation in the fellowship of Christ’s sufferings. But he or she is willing to pay this price because their hearts are set not on this world, but on the world that is to come.
Some of you here are not Christians. And it is very important for you to hear this. We do not tell you that becoming a Christian will solve all your problems. It will solve some of them, to be sure, and the greatest of them – your estrangement from God, the guilt of your sins, the threat of God’s wrath – but it will bring other problems. And we do not urge you to believe in Christ and be saved because life will become easy for you if you do. It can be very hard to be a Christian in this world. We urge to believe in Christ, rather, because he is the way, the truth, and the life, and the salvation that he has to give you, and he alone, the eternal life, the knowledge of himself, the annihilation of sin, is so wonderful, so surpassingly wonderful, that it is worth many, many times whatever it will cost you to become his follower.
A case was brought to the elders in Geneva in the time of the Reformation. A pious woman, who was being badly treated by her husband on account of her faith and godliness, had asked if she could leave her husband and come to Geneva and find rest for her conscience and liberty to practice her faith unhindered. (It is, by the way, always a very good sign of the spirit of true submission to God when a Christian submits to the judgment of the elders of the church. It is convincing proof that he or she really does want to do the right thing and is not simply seeking a way to do what he or she wants.)
The decision the elders gave was full of pastoral tact and the spirit of sympathy, but it breathed an unapologetic determination to follow Holy Scripture wherever it led. In their letter back to her they commiserated with the unfortunate woman, they gave her encouragements for her faith, and then, in this gentle way, they began to give their answer to her specific question.
“Nevertheless, since she has asked for our counsel regarding what is permissible, our duty is to respond, purely and simply, on the basis of what God reveals to us in his Word, closing our eyes to all else. For this reason, we beg her not to take offense if our advice does not correspond with her hope. For it is necessary that she and we follow what the Master has ordained, without mingling our desires with it.” [Calvin’s Ecclesiastical Advice, 131-132]
Then they take her to our text, to this very text in 1 Cor. 7, and remind her that the believing spouse is to remain in a spiritually mixed marriage. They make this interesting pastoral point:
“Without a doubt Paul emphasizes this, fully knowing the suffering each party may be experiencing. For at that time the pagans and the Jews were not less poisoned against the Christian religion than the papists are today. But St. Paul commands the believing partner, who continues to persevere in the truth of God, not to leave the partner who resists God.” 
But they do not stop there. They give this woman a reason, a justification for taking this hard road. “In brief, we ought so to prefer God and Jesus Christ to the whole world that fathers, children, husbands, and wives cease to constitute something we value.” They use the same extravagant language the Bible often does. And, then, there is the unbelieving husband to think of.
“…a believing wife ought not to relinquish her hope without striving and trying to direct her husband toward the road of salvation. No matter how great his obstinacy might be, she must not let herself be diverted from the faith; rather she must affirm it with constancy and steadfastness – whatever the dangers may be.”
Now, it is very interesting, and, I think, reveals the true art of biblical interpretation, that the elders go on to say that if the woman comes to fear for her life, then she may take refuge in flight and they would not regard that as an unlawful divorce. But, how much would have to be endured before it ever came to that; if it ever came to that.
Imagine that woman receiving that letter and opening it, perhaps her hands trembling with anticipation, wondering what it would say and if she would have been given liberty to leave her brute of a husband. And then see her reading it paragraph after paragraph, until she came to the end.
“Therefore she needs to pray for God to strengthen her, then she needs to fight more valiantly than she has, drawing upon the power of the Holy Spirit, to show her husband her faith, doing so in gentleness and humility, explaining to him that she must not offend God for the sake of pleasing him.” 
Did her heart sink while she read that letter, or did she feel a new resolve building within her. Either way, she got sound, Pauline, biblical advice. It was sound advice because it artfully applied Paul’s teaching to that woman’s situation. It got both Paul’s commandment right and the underlying motive and principle. And if her heart was right with God, if she loved God and was willing to suffer for Christ’s sake, she would have heard the clear, bell-like tone of the truth in what she had read from those Genevan elders.
As Augustine has it in his Confessions, “He is the best servant, who looks not so much to hear that from [God] that he himself wants, as rather to want that which he hears from [God].” Or as we read in Proverbs, “Above all else, guard your heart, for from out of it flow the issues of life.”
And, if, as we believe, she followed the advice that she was given, now, in heaven, that dear woman is so happy that she did!