Can these bones live? — The question is put to the prophet in order to emphasise the human impossibility of that which is immediately brought about by the Divine omnipotence. (Comp. Matthew 9:5-6.) It was precisely this teaching which the people needed. As they had formerly refused to believe his announcements of impending judgment, so now that this had come, they were utterly incredulous in regard to his declarations of future blessing. It seemed to them impossible, and what they needed to be taught was that “what is impossible with man is possible with God.”
Thou knowest. — The prophet sees the natural impossibility, yet perceives that there must be some deeper reason for the question, and therefore replies in these words. It may be, too, that the question thus asked, before its object is suggested, connected itself in his mind with the thought of the literal resurrection of the dead and the difficulties it suggests.