Sharp words of rebuke confront a fallen leader, contrasting a past filled with spiritual strength against a present defined by despair. The primary approach among commentators is that the focus here is on Job's past behavior. In the days when his standing was high, he acted as a moral guide for the masses [ביאור שטיינזלץ, רמב״ן]. He would correct those who complained or spoke out against Heaven [רש״י, מצודת דוד]. Job taught people who were suffering to accept their pain from God with joy, bringing peace to their troubled minds during times of sadness [רמב״ן, חומת אנך].
When people experienced a lack of resolve [מצודת ציון], Job was there to encourage them through their hard times [ביאור שטיינזלץ]. He used words of moral instruction to strengthen those whose faith in God had weakened [מצודת דוד]. If someone was afraid of divine judgment or an approaching disaster, Job would calm them, assuring them they had nothing to fear [רש״י]. This specific type of weakness he addressed was a preliminary and relatively light stage of faltering, occurring before any total collapse of the spirit [מלבי״ם].
The purpose of recalling this history is to hold a critical mirror up to Job. He preached beautifully when he was a healthy man, but he fails to practice what he preached now that hardship has come upon him [אלשיך]. Now that the pain touches him personally, he forgets the very words of comfort he offered to others. He panics at the sudden shift in judgment and blames his situation on mere luck [רמב״ן, חומת אנך]. Job cannot claim that his suffering is exceptionally unique, for he guided many who surely faced similar difficulties. Likewise, he cannot excuse his breakdown on physical weakness, because he himself knew exactly how to cure that same weakness in others [אלשיך].
However, a completely different approach views this not as a reflection on the past, but as a direct result of the present. According to this perspective, the focus is not on the guidance Job once gave, but on the fact that right now, as he denies divine providence and breaks down, his behavior serves as a living moral lesson for the public. People see that the moment tragedy reached him, he failed the test. From this, they conclude that all his past reverence for God stemmed only from a desire for reward and personal benefit, rather than true awe. Ironically, it is Job's rapid downfall that ultimately justifies God's judgment and prevents others from losing their faith in divine providence [מלבי״ם].