Job 21:5

Mark me - Margin, “look unto.” Literally, “Look upon me. That is, attentively look on me, on my sufferings, on my disease, and my losses. See if I am a proper object of repreach and mockery - see if I have not abundant reason to be in deep distress when God has afflicted me in a manner so unusual and mysterious.

And be astonished - Silent astonishment should be evinced instead of censure. You should wonder that a man whose life has been a life of piety, should exhibit the spectacle which you now behold, while so many proud contemners of God are permitted to live in affluence and ease.

And lay your hand upon your mouth - As a token of silence and wonder. So Plutarch, de Iside et Osiride, “Wherefore, he had laid his finger on his mouth as a symbol of silence and admiration - ἐχεμυθίας καὶ σιωπῆς σύμβολον echemuthias kai siōpēs sumbolon.”