Is this your son, who ye say was born blind? — The “ye” is emphatic; ye say he was born blind, as opposed to us, for we do not believe it. There are three questions. Is this your son? Do ye still say that he was born blind? which is incredible, as he now possesses the faculty of sight (John 9:32). If you do, how do you account for the fact that he now sees?
How then doth he now see? — Their question means — “How does it come to pass, since he was born blind, that he all at once seeth?” The word rendered “now,” here and in John 9:21; John 9:25, conveys the idea of the suddenness of the change which had taken place.