Mark me, and be astonished, and lay your hand upon your {c} mouth.

(c) He charges them as though they were not able to comprehend his feeling of God's judgment, and exhorts them therefore to silence.

Wesley's Notes

21:5 Mark - Consider what I am about to say concerning the prosperity of the worst of men, and the pressures of some good men, and it is able to fill you with astonishment. Lay, and c. - Be silent.

King James Translators' Notes

Mark...: Heb. Look unto me

Jamieson-Fausset-Brown Bible Commentary

5. lay . hand upon . mouth-(Pr 30:32; Jud 18:19). So the heathen god of silence was pictured with his hand on his mouth. There was enough in Job's case to awe them into silence (Job 17:8).

Matthew Henry's Concise Commentary

21:1-6 Job comes closer to the question in dispute. This was, Whether outward prosperity is a mark of the true church, and the true members of it, so that ruin of a man's prosperity proves him a hypocrite? This they asserted, but Job denied. If they looked upon him, they might see misery enough to demand compassion, and their bold interpretations of this mysterious providence should be turned into silent wonder.