For the bed is shorter... — The image represents vividly a policy that ended in failure. Hezekiah’s counsellors had “made their bed,” and would have to lie on it, in their Egyptian alliance, but it would not meet their wants. Bed and blankets would be all too scanty, and leave them in a restless disquietude.
Related Commentaries of Isaiah 28:20
Isaiah 28:20
20 For the bed is shorter than that a man can stretch himself on it: and the covering narrower than that he can wrap himself in it.