Jesus permitted divorce in cases of sexual immorality (Matthew 19:9 — the 'exception clause') and Paul permits separation when an unbelieving spouse deserts (1 Corinthians 7:15 — the 'Pauline privilege'). Outside these grounds, the biblical picture is that divorce is contrary to God's design and remarriage after unwarranted divorce constitutes adultery. This is a pastorally complex question where the church has both a truth obligation and a grace obligation. 45/100 Caution.
Matthew 19:3-9 is the primary text: the Pharisees asked Jesus whether it is lawful to divorce a wife for any reason. Jesus replied by citing Genesis 2:24 (the two become one flesh) and concluding: "Therefore what God has joined together, let no one separate." When they pressed him about Moses's allowance for divorce certificates (Deuteronomy 24:1-4), Jesus responded: "Moses permitted you to divorce your wives because your hearts were hard. But it was not this way from the beginning. I tell you that anyone who divorces his wife, except for sexual immorality, and marries another woman commits adultery."
The "exception clause" (except for sexual immorality / porneia) is the crux of the debate. Most evangelical scholars agree it establishes sexual immorality as a legitimate ground for divorce. The debate is whether remarriage is permitted after divorce on these grounds — Jesus says "and marries another woman commits adultery," which most take to mean: remarriage after unwarranted divorce is adultery, with the implication that remarriage after warranted divorce is not.
1 Corinthians 7:15 adds a second ground: "But if the unbeliever leaves, let it be so. The brother or the sister is not bound in such circumstances; God has called us to live in peace." This "Pauline privilege" — desertion by an unbelieving spouse — is widely recognized by evangelical scholars as a legitimate ground for divorce. The question again is whether remarriage is permitted.
The Church must hold two things simultaneously: God's design for lifelong marriage is clear and should be taught without apology, AND God's grace for those who have experienced divorce — through their own sin or another's — is real and should be extended without qualification. Many Christians who have divorced and remarried did so without full biblical understanding, under pastoral counsel that was wrong, or in situations of genuine abuse or abandonment.
The answer to past divorce is not second divorce. The answer is to live faithfully in present circumstances while pursuing the reconciliation, counseling, and community that God provides. See our Is It a Sin? hub and our guide on Is It a Sin to Be Angry? The GotQuestions treatment of divorce and remarriage provides comprehensive biblical analysis. The Gospel Coalition's article on divorce provides additional depth.
For the broader biblical framework on marriage, see our guide What Does the Bible Say About Marriage?