13. Is it a small thing?—Is it not enough for you (Nu 16:9)? The allusion to "David" is in order to contrast his trust in God with his degenerate descendant Ahaz' distrust.
weary—try the patience of.
men—prophets. Isaiah as yet had given no outward proof that he was from God; but now God has offered a sign, which Ahaz publicly rejects. The sin is therefore now not merely against "men," but openly against "God." Isaiah's manner therefore changes from mildness to bold reproof.