Answer
When discussing what the Bible says about divorce, it is important to keep in mind the words of Malachi 2:16, “I hate divorce,” says the Lord God. Whatever grounds the Bible possibly gives for divorce, that does not mean God desires a divorce to occur in those instances. Rather than asking “is ______ a grounds for divorce,” often the question should be “is _______ grounds for forgiveness, restoration, and/or counseling?”
The Bible gives two clear grounds for divorce: (1) sexual immorality (Matthew 5:32; Matthew 19:9) and (2) abandonment by an unbeliever «But if the unbelieving depart, let him depart. A brother or a sister is not under bondage in such cases: but God hath called us to peace. », (1 Corinthians 7:15). Even in these two instances, though, divorce is not required or even encouraged. The most that can be said is that sexual immorality and abandonment are grounds (an allowance) for divorce. Confession, forgiveness, reconciliation, and restoration are always the first steps. Divorce should only be viewed as a last resort.
Are there any grounds for divorce beyond what the Bible explicitly says? Perhaps, but we do not presume upon the Word of God. It is very dangerous to go beyond what the Bible says «And these things, brethren, I have in a figure transferred to myself and to Apollos for your sakes; that ye might learn in us not to think of men above that which is written, that no one of you be puffed up for one against another. »,
(1 Corinthians 4:6). The most common reasons for divorce that people ask about are spousal abuse (emotional or physical), child abuse, addiction to pornography, drug/alcohol abuse, criminal activity/imprisonment, and financial mismanagement (such as through a gambling addiction). None of these can be considered explicit biblical reasons for divorce.
However, that does not necessarily mean that none of them are reasons for divorce that God would approve of. For instance, it is hard to believe that it would be God’s will for a wife to stay with a husband who physically abuses her and/or their children. In such a case, the wife should definitely separate herself and the children from the abusive husband. Nevertheless, even in such a scenario, a period of separation with the aim of repentance and reconciliation should be the goal, not necessarily immediately initiating divorce proceedings. Please note, when we say that the aforementioned reasons are not biblical grounds for divorce, we are certainly not suggesting that a man/woman whose spouse is involved in such behaviors should stay in that situation. If there is any danger to oneself or the children, separation is a wise and appropriate step.
Another perspective on this matter is to distinguish between biblical grounds for divorce and biblical grounds for divorce and remarriage. Some interpret the two biblical grounds for divorce mentioned earlier as the only grounds for remarriage after a divorce, but permit divorce without remarriage in other cases. While this interpretation is plausible, it appears to be too close to assuming the will of God. For further information, please refer to the following two articles:
https://www.gotquestions.org/divorce-remarriage.html
https://www.gotquestions.org/divorced-remarry.html
In conclusion, what are the biblical reasons for divorce? The answer is sexual immorality and abandonment. Are there other reasons for divorce besides these two? Perhaps. Is divorce ever to be taken lightly?
Is divorce the first option when a marriage is facing challenges or employed as the first recourse? Absolutely not. God is capable of changing and reforming any individual. God is capable of healing and renewing any marriage. Divorce should only occur in cases of repeated and unrepentant heinous sin.