Job 18:4 (ESV)

4 You who tear yourself in your anger, shall the earth be forsaken for you, or the rock be removed out of its place?

In Bildad’s eyes, the principle of retribution (God rewards righteousness and punishes wickedness) is as permanent and stable as the earth itself. Job is mad and arrogant to try and overthrow this principle for the sake of his so-called innocence. It is not God who is tearing Job apart (Job 16:9). Rather, Job is tearing himself apart through his sinful anger.