A.T. Robertson Commentary Matthew 5:32

"but I say unto you, that every one that putteth away his wife, saving for the cause of fornication, maketh her an adulteress: and whosoever shall marry her when she is put away committeth adultery." — Matthew 5:32 (ASV)

Saving for the cause of fornication (παρεκτος λογου πορνειας). An unusual phrase that perhaps means "except for a matter of unchastity." "Except on the ground of unchastity" (Weymouth), "except unfaithfulness" (Goodspeed), and is equivalent to μη επ πορνεια in Mt 19:9. McNeile denies that Jesus made this exception because Mark and Luke do not give it. He claims that the early Christians made the exception to meet a pressing need, but one fails to see the force of this charge against Matthew's report of the words of Jesus. It looks like criticism to meet modern needs.