Albert Barnes Commentary Job 27:5

"Far be it from me that I should justify you: Till I die I will not put away mine integrity from me." — Job 27:5 (ASV)

God forbid - לי חלילה châlı̂ylâh lı̂y. “Far be it from me.” Literally, “It would be profane to me;” that is, I would regard it as unholy and profane; I cannot do it.

That I should justify you - That I should admit the correctness of your positions, and should concede that I am a hypocrite. He was conscious of integrity and sincerity, and nothing could induce him to abandon that conviction, or to admit the correctness of the reasoning which they had pursued in regard to him. Coverdale (1535 AD) has given this a correct translation, “God forbid that I should grant your cause to be right.”

Till I die I will not remove mine integrity from me - I will not admit that I am insincere and hypocritical. This is the language of a man who was conscious of integrity, and who would not be deprived of that consciousness by any plausible representations of his professed friends.