The Bible has far fewer things to say about remarriage than it does about divorce. We will look, then, at the few verses that directly speak to this issue. Foundationally, from these texts we may draw out the principle that all Biblically qualified divorces permit the victims of a broken marriage to remarry.
There are two different sets of texts in the New Testament regarding remarriage. There are some that indicate a spouse is free to remarry, and some that clearly state a spouse is not free to remarry. In fact the latter set of texts is even more pointed, sometimes equating remarriage to adultery. It’s important to note that there are two different directives because, according to the Bible, there are two types of divorce: (1) Acceptable and (2) Un-acceptable. That is to say, God allows divorces for the victims of broken marriage vows; but He does not allow divorces for any other reason. So, like cases of divorce, God allows remarriage for some, but not for others.
We have already seen how the Old Testament handled this issue with a “certificate of divorce.” Those women in the OT who were neglected or abandoned by their husbands were permitted to divorce and given a certificate that made them eligible for remarriage without the fear of their previous husbands coming back to lay claim on them again. On the other hand, Malachi 2:16 indicates a type of divorce that God does not permit, “the man who hates his wife and divorces her.”
Likewise, Paul says in 1 Corinthians 7 that a spouse who is abandoned is not “enslaved.” The meaning here parallels the use of the divorce certificate to indicate the freedom of the neglected spouse. They are free to remarry if they so choose. The language parallels verse 39 where the widow is not “bound” to her deceased husband, but is “free to be married to whom she wishes.” Yet, Paul also says that a woman who divorces her husband should remain unmarried or be reconciled to her husband (v. 11). The difference is one of context. The former relationship reveals two believers with no evidence of covenant violations. The latter reveals an unbelieving spouse who has abandoned his family. The different contexts require different boundaries for remarriage.
The most significant passage on remarriage in the New Testament comes from Jesus himself who compares remarriage to adultery. In Matthew 5:31-32 Jesus states plainly that divorces “makes a [woman] commit adultery” and the man who marries a divorced woman commits adultery with her. The language here is strange, but it is at least clear that Jesus has in mind remarriage and its association with sexual intimacy within marriage. Because Matthew 19 is Jesus’ more expounded teaching on divorce we need to read this passage in light of the other. Even here, Jesus alludes to the debate over Deuteronomy 24:1 (with the phrase “except for sexual immorality”). Thus we may conclude that he is again refuting the “Any Cause” approach to divorces. In such cases there is not Biblical grounds for divorce and remarriage would be adultery.
Within the Biblical worldview, then, the way we determine whether someone is eligible for remarriage after divorce is by looking at the nature of their divorce. If the divorce was on Biblical grounds and they are the victim of that broken marriage then they are eligible for remarriage. If they are the cause of the broken marriage they are not eligible for remarriage. If their divorce was not Biblical then they are not eligible for remarriage. Only victims of broken vows who apply for Biblical divorces are eligible for biblical remarriages.
What about those who have already remarried after an unbiblical divorce?
For those who have already remarried after an unbiblical divorce you are required now to be faithful to your second marriage partner. The notion that someone is in a state of perpetual adultery because of their second marriage is not corroborated by this passage. Jesus teaches that the initial act of remarriage after an unbiblical divorce is adultery, but another divorce is not the solution. Two wrongs do not make a right. Any believer who is now in a marriage after an unbiblical divorce is called by God to love their spouse faithfully and fulfill their covenant obligations just as they should have in their first marriage. There is forgiveness for both the unbiblical divorce and the unbiblical remarriage.
Summary: Biblical remarriage is only open to those who are victims of broken marriages and apply for Biblical divorces. Those who have already remarried despite having no Biblical grounds for divorce are to remain married to their “new” spouse, and to seek to fulfill all their covenant obligations to that spouse. They are not to divorce again. There is grace and forgiveness for unbiblical divorces and unbiblical remarriages.