Job 37:20

Shall it be told him that I speak? - Still the language of profound awe and reverence, as if he would not have it even intimated to God that he had presumed to say anything in regard to him, or with a view to explain the reason of his doings.

If a man speak - That is, if he attempt to speak with God; to argue a case with him; to contend with him in debate; to oppose him. Elihu had designed to reprove Job for the bold and presumptuous manner in which he bad spoken of God, and for his wish to enter into a debate with him in order to vindicate his cause. He now says, that if anyone should attempt this, God had power at once to destroy him; and that such an attempt would be perilous to his life. But other interpretations have been proposed, which may be seen in Rosenmuller, Umbreit, and Lee.

Surely he shall be swallowed up - Destroyed for his presumption and rashness in thus contending with the Almighty. Elihu says that on this account he would not dare to speak with God. He would fear that he would come forth in his anger, and destroy him. How much man by nature instinctively feels, when he has any just views of the majesty of God, that he needs a Mediator!