A.T. Robertson Commentary Matthew 19:10

"The disciples say unto him, If the case of the man is so with his wife, it is not expedient to marry." — Matthew 19:10 (ASV)

The disciples say unto him (λεγουσιν αυτω ο μαθητα). "Christ's doctrine on marriage not only separated Him τοτο χαελο from Pharisaic opinions of all shades, but was too high even for the Twelve" (Bruce).

The case (η αιτια). The word may refer to the use in verse 3 "for every cause." It may have a vague idea here = ρες, condition. But the point clearly is that "it is not expedient to marry" (ου συμφερε γαμησα) if such a strict view is held. If the bond is so tight a man had best not commit matrimony. It is a bit unusual to have ανθρωπος and γυνη contrasted rather than ανηρ and γυνη.