Eliphaz' Prophecy

I was reading Job today, and I came across a verse that caused me to pause.

Job 22:30 - "He will deliver one who is not innocent, and he will be delivered through the cleanness of your hands."

Context: Eliphaz accuses Job of not being so righteous as he claims (actually he accuses him of some pretty terrible stuff), and then tells him that all he needs to do is turn to God, hide His word in his heart, and God will restore him. He finishes his exhortation with this verse.

I pondered to myself what this could mean. The most obvious answer I could think of was that Job would save an unrighteous man by virtue of his own righteousness. I thought about how this could happen. And then I remembered how Job ends...

[Spoiler Alert!]
After God gives Job a thorough rundown about who is God and who is not, Job confesses that he has no case before God. God then turns to Eliphaz and tells him that He is not pleased with him and his friends because they have not spoken what is right about God as Job has. The solution? Go to righteous Job and ask him to make sacrifice on their behalf, because God will accept Job. And so they do. Whoa... do you see what just happened? God saved him who was not innocent, and He did it by the cleanness of Job's hands. Dude Eliphaz, it was you! You are the one who is not innocent! You are the one who will be saved by the cleanness of Job's hands! For thirty-some-odd chapters Eliphaz and his friends have sat and accused Job, exhorted him, insulted him, trivialized his suffering, gotten defensive, etc. And all this time, they were the unrighteous ones. And yet it was Job who was made to suffer. It's completely opposite of "the world according to Eliphaz".

It blows my mind. Does God not have a sense of irony?