While reading &/ discussing in this thread, keep in mind that we are created to be reflections of God who created to us in His image and likeness.
Whatever is not of faith is sin. Romans 14:23
Knowingly transgressing the law is sin. 1John 3:4
Knowing (and able) to do good and not doing it is sin. James 4:17
All unrighteousness is sin. 1John 5:17
There is another aspect of sin which is spoken of as in Romans 7; this is the unlawful desires which are in the flesh (Romans 7:17, 20) which is not condemnable unless acted upon.
Sin has a dual concept which needs to be understood. There is intentional sin and unintentional sin.
Unintentional sin is called objective sin. Unintentional sin is objective because it is evident to others as sin, but the one who commits it is not aware of it; his heart has not committed the sin. Since he is not aware of it; his heart is innocent, he is not accountable to it, and therefore, he cannot be condemned for it.
Intentional sin is both objective and subjective because it is evident to both the witnesses and the one who commits it. Moreover, intentional sin may not even be a sin to others even though it is sin for the one who commits it, thus the reason being subjective. It is subjectively sin because while others are not aware of it being sin, the one who thinks it is, feels condemned in his own conscience because he did something against it; and for that reason it is sin (Rom 14:23).
The reason for these distinctions is because God looks at the heart (1 Samuel 16:7). He cares if the heart is involved or not. As with unintentional objective sin, ones heart is not involved and one remains innocent and not liable for judgment while intentional, subjective sin has the heart involved and one is guilty, liable for judgment.
There are Scripture references for unintentional sin such as Leviticus 4 & 5:15-18. With these Scriptures, the reason for the sin offering is not that the one who sins in ignorance is condemned and needs atoned for, but that he needs to acknowledge the law as being broken once he finds out that he did sin. However, if one never finds out that he has sinned, there will never be an offering for that sin.
Leviticus 4:14 When the sin...is known, then the congregation shall offer a young bullock for the sin...
Leviticus 4:23 Or if his sin...comes to his knowledge; he shall bring his offering.
Leviticus 4:28 Or if his sin...comes to his knowledge: then he shall bring his offering.
The questions are; how does one make an offering for sin if he does not know the need for it? How can he repent from the unknown? And if he doesn't know that he sinned, how is his heart involved to be guilty? When sin is unknown, how could one repent?
Even though someone did unintentionally sin and is objectively guilty, he remains subjectively innocent and that is all God cares about. However, when the sin is found out, he remains uncondemned but he still must repent as to never doing it again.
Job 42:3 ...therefore have I uttered what I understood not; things too wonderful for me, which I knew not.
This means that Job spoke only of that which he had knowledge of at the time of utterance; he did not understand yet what he was to learn latter on. One is only accountable to the knowledge of which he has vat that moment.
If Job spoke against what he did know, then he would be guilty, but he didn't do that.
According to Scripture, hearing and seeing are often the antithesis to each other.
Job 42:5 I have heard of you by the hearing of the ear: but now my eye sees you
In other words, Job is saying, "I have only heard before of thee by tradition or from imperfect information, but now I have such a discovery and revelation of thee as I have never had before."
Job (42:5) did not know God before as he does now. He was only speaking from the knowledge of which he possessed at the time and this is not condemnable. It would only be condemnable if he knew better at the time of utterance.
Sin which is condemnable is always intentional, but unintentional sin is not condemnable, therefore Job was blameless.
Job 42:6 Therefore I abhor myself, and repent in dust and ashes.
Since Job was innocent when he spoke from only the knowledge which he had, the knowledge of what he now learns does not become held against him. However, as he learns the truth of God in a brighter light, his repentance is only implying that he will not say what he had said before, knowing what he knows now.
With Job, we may understand the sin of ignorance is not condemnable, but it is still important to realize the gravity of it to never do again now that it is known to be such.