Job 33:19

He is chastened also with pain -As another means of checking and restraining him from the commission of sin. When the warnings of the night fail, and when he is bent on a life of sin, then God lays him on a bed of pain, and he is brought to reflection there. There he has an opportunity to think of his life, and of all the consequences which must follow from a career of iniquity. This involves the main inquiry before the disputants. It was, why people were afflicted. The three friends of Job had said that it was a full proof of wickedness, and that when the professedly pious were afflicted it was demonstrative of insincerity and hypocrisy.