“We cannot do such a thing,” they said. “To give our sister to an uncircumcised man would be a disgrace to us.
Jacob's sons, when they heard of the injury done to Dinah, showed a very great resentment of it, influenced perhaps rather by jealousy for the honour of their family than by a sense of virtue. Many are concerned at the shamefulness of sin that never lay to heart the sinfulness of it.
Commenting on Genesis 34:6-17
And they said unto them,.... Levi and Simeon, to Hamor and Shechem: we cannot do this thing, to give our sister to one that is uncircumcised; not that there was any law against it at that time; and there were, on the other hand, precedents for it both in Isaac and Jacob, who had married the daughters of uncircumcised persons; nor indeed do they plead...
And they said unto them, We cannot do this thing, to give our sister to one that is uncircumcised; for that [were] a reproach unto us: (c) They used the holy ordinance of God a means to accomplish their wicked purpose. (d) As it is abomination for those who are baptized to be joined to infidels.