Marriage - Unlawful vs. Fornication


An evangelical friend of mine challenged my assertion the other day that divorce is against the will of God, period. I pointed to five different places in the New Testament alone that support this. The first of these, though, Matthew 5:32, caused me a little consternation. Of the five, only Matthew’s two passages actually have a caveat, or exception, to the rule. In my NAB translation, the 5:32 verse reads thusly:
“But I say to you, whoever divorces his wife (unless the marriage is unlawful) causes her to commit adultery, and whoever marries a divorced woman commits adultery.”

My understanding of “unlawful” was to refer to things like incest, etc. That is fine, and the rule against divorce seems pretty clear.

However, if you look at a bunch of other translations, you get something quite different:

“But I say to you, that whosoever shall put away his wife, excepting the cause of fornication, maketh her to commit adultery: and he that shall marry her that is put away, committeth adultery.”

Latin Vulgate:
“ego autem dico vobis quia omnis qui dimiserit uxorem suam excepta fornicationis causa facit eam moechari et qui dimissam duxerit adulterat”

Revised Standard Version:
“But I say to you that every one who divorces his wife, except on the ground of unchastity, makes her an adulteress; and whoever marries a divorced woman commits adultery.”

King James:
“But I say unto you, That whosoever shall put away his wife, saving for the cause of fornication, causeth her to commit adultery: and whosoever shall marry her that is divorced committeth adultery.”

You get the idea. Fornication, or adultery, to me is quite different
than an “unlawful” marriage. So where does this difference come from?

God Bless,


The translations “fornication” and “unchastity” here do not refer to adultery but rather to activity within an unlawful marriage. So these translations are not inconsistent with “unlawful” - unlawful marriage results in fornication/unchastity.

The RSV-CE contains this footnote: "unchastity: The Greek word used here appears to refer to marriages that were not legally marriages because they were either within the forbidden degrees of consanguinity (Lev 18:6-16) or contracted with a Gentile. The phrase *except on the ground of unchastity * does not occur in the parallel passage in Lk 16:18. See also Mt 19:9 (Mk 10:11-12), and especially 1 Cor 7:10-11 which shows that the prohibition in unconditional.”

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