Adam Clarke on Luke 7:31

And the Lord said - Almost every MS. of authority and importance, with most of the versions, omit these words. As the Evangelistaria (the books which contained those portions of the Gospels which were read in the Churches) began at this verse, the words were probably at first used by them, to introduce the following parable. There is the fullest proof that they never made a part of Luke's text. Every critic rejects them. Bengel and Griesbach leave them out of the text.