ציטירנדיקער פּירוש אויף תהילים 37:31

In this way he also justifies his reproof of Job at the beginning of his first speech, when he had said: 'Was not your own security the reason for your piety?' (Job 4:6). For the essence of correct worship is that it should be performed without any expectation of repayment or fear of retribution, and in this Job had sinned, Therefore his steps faltered (Psalms 37:31), and God poured His wrath upon him (Lamentations 4:11).

As further evidence that Job had not been completely perfect in his worship, Eliphaz cites the fact that he had begun to complain against God and to deny principles of faith the moment the suffering started. This showed that his fear of God had not been genuine and had only been motivated by love of reward and fear of punishment. For someone who genuinely fears the Lord, his steps do not falter (Psalms 37:31) when He rebukes him; unlike Job who preaches nonsense, (Job 35:16) turning everything upside down (Ch.4:2, 4:7).

— is that the exchange mechanism is just a prophylactic; that when God foresees that a righteous person is by his nature likely to sin at some time in the future, He makes him suffer in advance, thereby bending his will (Leviticus 26:41) and preventing him from slipping; (Psalms 37:31) and then the Lord will again rejoice over him for good (Deuteronomy 30:9).