If I sin - The object of this verse and the following is, evidently, to say that he was wholly perplexed. He did not know how to act. He could not understand the reason of the divine dealings, and he was wholly unable to explain them, and hence, he did not know how to act in a proper manner. It is expressive of a state of mind where the individual wishes to think and feel right, but where he finds so much to perplex him, that he does not know what to do. Job was sure that his friends were not right in the position which they maintained - that he was a sinner of enormous character, and that his sufferings were proof of this, and yet he did not know how to answer their arguments. He desired to have confidence in God, and yet he knew not how to reconcile his dealings with his sense of right. He felt that he was a friend of God, and he did not know why he should visit one who had this consciousness in this distressing and painful manner. His mind was perplexed, vacillating, embarrassed, and he did not know what to do or say. The truth in this whole argument was, that he was more often right than his friends, but that he, in common with them, had embraced some principles which he was compelled to admit to be true, or which he could not demonstrate to be false, which gave them greatly the advantage in the argument, and which they pressed upon him now with overwhelming force.
Then thou markest me - Dost carefully observe every fault. Why he did this, Job could not see. The same difficulty he expressed in Job 7:17-19; see the notes at that place.
And wilt not acquit me - Wilt not pardon me. Job did not understand why God would not do this. It was exceedingly perplexing to him that God held him to be guilty, and would not pardon him if he had sinned. The same perplexity he expressed in Job 7:21; see the note at that verse.