A sister in the church told me that the word unfaithful can mean other
things besides being sexually unfaithful, in terms of divorce. But from
what I understand you can only divorce if your spouse has been sexually
unfaithful. What does God (the Bible) say?

I will assume that you are referring to the text of Matthew
5:32 and/or Matthew 19:9. I will quote the latter: “I tell you that the
truth, anyone who divorces his wife except for marital unfaithfulness, and
marries another woman, commits adultery.” Your question could be answered
on a number of levels. What Greek word is used for “unfaithfulness” in
the text? What is the range of meaning of this word in general? What
other Greek words can be used as synonyms, what are their meanings, and
why did Matthew/Jesus choose this particular word? I am going to assume
that you are not interested in some sort of exegesis involving the meaning
of individual Greek words. A good rule of interpretation (hermeneutics)
is that the immediate context of a particular passage should be used to
interpret the meaning of a text. I believe that this passage is so plain
in its meaning that no fancy exegesis is needed to interpret it.

Let us, therefore, consider the meaning of the passage in its
own context. Jesus tells us that anyone who marries another woman outside
the just cause of unfaithfulness on the part of his wife commits
adultery. The context tells us clearly that he is talking about marriage,
but also about the sexual act (“commits adultery”). In other words, the
context of this passage tells us in a fairly straightforward way that
Jesus is talking about a spouse who commits adultery being the only
acceptable justification for a follower of Jesus divorcing their spouse
and remarrying another.

I get the sense that there is more than a simple curiosity to
correctly interpret the passage behind this questions. I get the
impression that there is a real situation behind your question, probably
on the part of your friend. I like to keep from expressing personal
opinion at this web site, but I will make an exception here. I believe
that some followers of Jesus, finding themselves in a very difficult
situation, are tempted to look for a way out of a difficult marriage
through divorce. If one moved away from the simple interpretation of this
passage, then almost any definition of the word “unfaithfulness” could be
used. “My husband looked at pornography once. I am therefore excused to
divorce him.” “My wife has not given the attention my children need. She
has not been faithful to our commitment to take care of our kids. She has
been unfaithful to me, so I feel it is right for me to divorce.” It is
easy to see where this line of reasoning could lead. The standard for
divorce would devolve into the same standard as the world. We should let
the simple and obvious meaning of what Jesus said stand.

I do not intend at all to minimize some of the extremely
difficult situations in which disciples of Jesus may find themselves. I
believe that separation for a time is occasionally justified. I also
believe that there are situations in which a spouse or children are in
physical or a very extreme sort of emotional danger which definitely could
justify separation, and perhaps even divorce, based on careful advice of
spiritual leaders. I would simply say that if one were to do such a
thing, I am open to the possibility that this might be the best thing to
do. However, in such a case, using Matthew 19:9 or Matthew 5:32 should
not be invoked as a justification for the divorce. The Bible is very
comprehensive, but it does not give a specific answer to every conceivable
situation. Besides, 1 Corinthians 7 implies that if a non-Christian
chooses to initiate divorce, even if marital unfaithfulness on their part
is not involved, the disciple is “not bound” in such a situation.

To summarize, for a disciple of Jesus in a marriage situation
which is not positive–who might be hoping for a better situation, I would
strongly advise against looking to Matthew 19:9 or Matthew 5:32 as a way
out. Do not pray, hoping that your spouse will become unfaithful so that
you will have an excuse to get out of an unfulfilling marriage. Do not
look for a way to reinterpret Matthew to allow for unfaithful to be
creatively applied to your situation. Trust in God, as is taught in 1
Corinthians 7 and 1 Peter 3:1-7. Who knows what God will be able to use
you to do? Having said that, if you find yourself in a situation which is
dangerous to yourself or to your children, seek wise counsel. You may
need to leave your situation. Do not feel at all guilty about doing what
is right, but do not use the Matthew passages in such a situation.

John Oakes