Here is the basis of my understanding of the subject.
Sin, as it was made plain at the time of the giving of the law, was divided into two categories, sins of ignorance, and what was denoted as presumptuous sin, that done with a "high hand", as defined in rabbinical writings. It is noteworthy to notice that ONLY "sins of ignorance" were provided the opportunity of forgiveness through the sacrificial system of sacrifices. There were NO sacrifices to be offered for sins that were denoted as being presumptuously committed, or with a "high-hand", according to the law, but rather only the fearful looking for of judgment and fiery indignation from God in such cases.
Alfred Edersheim, in the book "The Temple", points this out on pp. 128. "Sins of ignorance" were not just sins that were committed through a want of knowledge as one might think, but included sins that one might have perceived as unintentional or by way of some weakness, or when the offender had not realized his guilt at the time of the infraction. It is also noted by rabbinical sources, that if one voluntarily confessed his sins, that the sin or sins would be classified as "sins of ignorance" as well. (Pp. 133) Some brought sacrifices every day to cover for their "sins of ignorance"! One can readily perceive that what the Jew understood as being "ignorance" is not synonymous with our notions of it today. Further more, God stated in Ac 17:30 "And the times of this ignorance God winked at; but now commandeth all men every where to repent:" What God once "winked at" as being the results of what might be denoted as "ignorance", He obviously looks at in a different light in this enlightened age. Of a truth, we conceive more clearly the law than those who lived at the time of the giving of the law. "To whom much is given, much is required."
Another notion that cannot be overlooked is the use of words when training the unenlightened or children. We see a cold stove and point to the burner and say to the young child “HOT!” The burner is not literally hot, but will be on occasion, and if one desires to see the child keep from serious injury, we tell them it is hot, even when in reality it is not. Such is the case with the word sin in the OT. When God told them, in this training period, that something was sin, I do not believe that the action in and of itself incurred the full penalty of the law, for they were in large part ignorant of the truth. God was training them to recognize the things He approved or disapproved of. Not until they understood the intrinsic element of the command apart from rewards or punishment was sin actually imputed to their actions. Only God knows when that happens. Hence the words from God, “Ac 17:30 "And the times of this ignorance God winked at; but now commandeth all men every where to repent:"
No where in the NT addressed to this enlightened generation, do we find any mention of sins of ignorance to my knowledge other than a reference to the ignorance existing in the OT. Although in common parlance one might speak of sin committed in ignorance, it in no wise undermines the clear teaching of Scripture that honest ignorance is not seen as sin by God. Sin is the willful transgression of a known commandment of God.
Yet another issue to consider is that the Jews had no place for any notion of original sin in their theology. This is duly noted by Alfred Edersheim in his book “The Life and Times of Jesus Christ the Messiah.” The only conclusion that can be justly drawn is that such sins of ignorance in no wise applies to infant and small children, as some might suggest, due to the fact they were considered innocent of sin altogether.