Job 32:9

So these three men ceased to answer Job, because he was righteous in his own eyes.

Then was kindled the wrath of Elihu the son of Barachel the Buzite, of the kindred of Ram: against Job was his wrath kindled, because he justified himself rather than God.

Also against his three friends was his wrath kindled, because they had found no answer, and yet had condemned Job.

Now Elihu had waited till Job had spoken, because they were elder

When Elihu saw that there was no answer in the mouth of these three men, then his wrath was kindled.