Adam Clarke on Acts 3:17

I wot - Οιδα, I know. Wot is from the Anglo-Saxon, to know; and hence wit, science or understanding.

Through ignorance ye did it - This is a very tender excuse for them; and one which seems to be necessary, in order to show them that their state was not utterly desperate; for if all that they did to Christ had been through absolute malice, (they well knowing who he was), if any sin could be supposed to be unpardonable, it must have been theirs. Peter, foreseeing that they might be tempted thus to think, and consequently to despair of salvation, tells them that their offense was extenuated by their ignorance of the person they had tormented and crucified. And one must suppose that, had they been fully convinced that this Jesus was the only Messiah, they never would have crucified him; but they did not permit themselves to receive conviction on the subject.