David Instone Brewer has written an excellent book on what the Bible has to say about divorce titled: Divorce and Remarriage in the Church: Biblical Solutions for Pastoral Realities. It is a great read because the author utilizes Biblical scholarship and presents it in an easy to understand way that it practically helpful for pastors and curious laymen. Much of the following comes from this book and if you want more information than I provide, I strongly suggest getting this book.For the rest, enjoy it here.
The following discussion will go through the valid reasons for divorce and out of this, valid reasons to remarry.
The Starting Point: God’s Heart
One thing is clear: God does not want divorce. In Matthew 19:1-12 and Mark 10:2-12 Jesus tells us “What God has joined together, let no man separate” and He sets this in the context of God’s original desire in creation and the two being one flesh. On top of this He tells us that the only reason why Moses permitted divorce in the first place was because the people’s hearts were hard. Ultimately, God desires reconciliation. The marriage relationship itself is said to be like the relationship between God and us (Eph 5:32) and God does not abandon us when times are difficult or painful (Rom 8:35; Jeremiah 32:40). Consider the book of Hosea where the Prophet’s relationship with his wife was a sign of God’s relationship with His people. Even though his wife turned to prostitution and others, he did not give up on her. God does not give up on us and this is the spirit in which we should first approach all considerations of divorce.