Matthew 19:9
"I tell you that anyone who divorces his wife, except for
marital unfaithfulness, and marries another woman commits
adultery."
It appears that Jesus gives Biblical grounds for divorce
in the event of marital unfaithfulness by a spouse.
Jesus was clarifying the law of Moses which allowed for
divorce. This was allowed as a concession because the
people's hearts were hard but Jesus makes it clear that they
should not remarry.
What is marital unfaithfulness? The Greek word is
porneia. It is where we get the English word
pornography. It appears 24 times in the New Testament.
In the King James version it is translated as fornication
every time. Other English translations in some way or
other imply that it is sexual immorality that is taking
place. So marital unfaithfulness should best be
understood as a sexual act outside of marriage.
Jesus never gives an explanation on why divorce is
allowed in the event of marital unfaithfulness. The
simplest solution is that a person who has been unfaithful
has already broken their marriage vow and therefore if their
spouse divorces them they are not the one guilty of breaking
the marriage vow.
Another explanation, although not without problems,
concerns the penalty for those caught in adultery.
Leviticus 20:10 states "If a man commits adultery with
another man's wife—with the wife of his neighbor—both the
adulterer and the adulteress must be put to death." If
an adulterer is put to death then there is no problem
divorcing or remarrying because a person is free to remarry
after their spouse has died.
The first problem with this is a logical one. If an
adulterer is put to death, there would be no need to go
through with a divorce unless it was symbolic.
The bigger problem is that this law was not practiced
evenly if it all. King David was not only an adulterer
but a murderer and did not face death. God actually
instructed Hosea to marry a prostitute of all people.
And Jesus prevents the Pharisees from upholding the law in
John 8 when they catch a woman in adultery. Instead of
judging her for her sin, He simply instructs her to go and
sin no more.
Marital unfaithfulness may be grounds for divorce and it
is certainly a sign of much deeper problems within a
marriage. This does not mean that the marriage can't
be salvaged however. It is cause for a divorce but God
still desires peace and harmony. He also desires a
repentant heart. A person who has been unfaithful in
their marriage deserves another chance if they are truly
repentant. King David committed awful sins but he was
still considered a man after God's own heart.
The truly difficult part of divorce and marital
unfaithfulness is that we can never be certain of a person's
heart. Only God knows a person's heart for certain.
For a marriage to withstand a partner being unfaithful, it
takes a tremendous amount of faith in a person's ability to
change and also in God to help that person and the marriage.