Job 13:10

He will surely reprove you, if ye do secretly accept persons.

God will surely rebuke those who in secret show partiality, giving unjust favor to one person over another.
The warning belongs to Job’s dispute with his friends, whose statements were generally true in themselves but were misapplied to his suffering.
In that setting it cautions against misjudging one who suffers by unfairly accusing him of sin.