Albert Barnes Commentary Job 31:33

"If like Adam I have covered my transgressions, By hiding mine iniquity in my bosom," — Job 31:33 (ASV)

If I covered my transgressions as Adam - That is, if I have attempted to hide or conceal them; if, conscious of guilt, I have endeavored to cloak my sins and to appear righteous. There has been a great variety of opinion about the meaning of this expression. The margin reads it, “After the manner of men.” Luther renders it, “Have I covered my wickedness as a man” - Habe ich meine Schalkheit wie ein Mensch gedeckt. Coverdale, “Have I ever done any wicked deed through which I shamed myself before men.” Herder, “Did I hide my faults like a mean man.” Schultens, “If I have covered my sin as Adam.” The Vulgate, Quasi homo - “as a man.” The Septuagint, “If when I sinned unwillingly (ᾶκουσίως akousiōs - inadvertently, undesignedly) I concealed my sin.” Noyes, “After the manner of men.” Umbreit, Nach Menschenart - “After the manner of men.” Rosenmuller, As Adam. The Chaldee, כאדם, meaning, as Rosenmuller remarks, as Adam; and the Syriac, As men.

The meaning may either be as people are accustomed to do when they commit a crime—referring to the common practice of the guilty to attempt to cloak their offenses—or the attempt of Adam to hide his sin from his Maker after the fall (Genesis 3:7–8). It is not possible to decide with certainty which is the correct interpretation, for either will accord with the Hebrew. But in favor of the supposition that it refers to the effort of Adam to conceal his sin, we may remark:

1. That there can be little or no doubt that that transaction was known to Job by tradition.
2. It furnished him a pertinent and striking illustration of the point before him.
3. The illustration is, by supposing that it refers to him, much more striking than on the other supposition.

It is true that people often attempt to conceal their guilt, and it may be regarded as a very general fact; but still, it is not so universal that there are no exceptions.

But here was a specific and well-known case, and one which, as it was the first, was also the most sad and melancholy instance that had ever occurred of an attempt to conceal guilt. It was not an attempt to hide it from man—for there was then no other man to witness it—but an attempt to hide it from God. From such an attempt Job says he was free.

By hiding my iniquity in my bosom - By attempting to conceal it so that others would not know it. Adam attempted to conceal his fault even from God; and it is common with people, when they have done wrong, to endeavor to hide it from others.