There is a distinct difference between ignorance and stupidity. Ignorance is defined as; Lacking knowledge or experience. Innocence is to have no knowledge of, to be without guilt, harmless, without knowledge of evil. Our title simply put is that to be ignorant of a matter makes you also innocent. The Tree of the knowledge of good and evil which was in the garden of Eden found in Genesis adresses this point. You can see why being ignorant of something also means you are innocent. On the other hand, stupidity is to lack normal intelligence, to be foolish, dull and boring. Stupidity is for the most part a decision. A stupid person though at some point has been exposed to the truth of a matter through the reality of the moment. But for whatever reason, chooses to not consider it and thus, chooses to remain silly and carefree, content to learn nothing. He then by refusing knowledge is stupid by choice and therefore, is not innocent of the matter at hand whether it be a legal matter or not. There are many examples in real life that make the point by the reality of any matter more clear, and is common to all human beings. For instance, I am currently learning to read music and play piano. Having never seriously tried to learn even the basics of music I entered ignorant of the subject and so, child-like in my approach to the wonder of making music. Because I am innocent through ignorance of the matters of reading and playing music, I enter it as a child. My teacher and I had a good laugh out loud moment when I mentioned that the beginners books I'm learning from are filled with cartoon-like characters who are throughout the books highlighting certain basics of music making. A person may be a genius in other matters, but when you are trying to grasp the basics of a matter you know nothing about, you enter child-like in the innocence of your ignorance. Besides the pure joy of learning something completely new, I understood while working with the sixty six keys divided by the center note of C, that center point is what separates treble to the right of center and bass to the left. You quickly come to realize that music is math. Besides the keyboard you use the five fingers of both hands, and for the different notes, there are designations by the look of the notes shown on the staff, and that each note is assigned a count. One count for quarter notes and up to four counts with whole notes. Again, math.
It is the same when you commit to learning anything new. When you first make the decision to follow Jesus to learn about the things and knowledge of God through His son, you to will begin as a child. A babe born of the Spirit you become as Jesus said, enter the Kingdom of God as a child. In other teaching Jesus told his disciples that because you are still as new babes in the family of God you will early on be fed the word in milk form. Only after grasping the basics will you be fed the solid meats, the deeper meanings of the Word. Remember, not knowing something doesn't make you stupid, it makes you innocent in your ignorance.