They could barely recognize Job: This expression shows how much Job had suffered (compare Isaiah 52:14; 53:3).
Job’s friends showed their grief and began to weep aloud, as if Job was dead.
Throwing dust sometimes showed anger or hate (see 2 Samuel 16:13; Acts 22:23). But here it showed grief (see Joshua 7:6; 1 Samuel 4:12; Nehemiah 9:1; Lamentations 2:10).