Ignorance
A bhikku asked Buddha whether there is one thing through the abandoning of which ignorance is abandoned and true knowledge arises.  Buddha answered : " Ignorance, bhikku, is that one thing through the abandoning of which ignorance is abandoned by a bhikku and true knowledge arises " . Ven. Bodhi states in a note to this passage: " Though it may sound redundant to say that ignorance must be abandoned in order to abandon ignorance, this statement underscores the fact that ignorance is the most fundamental cause of bondage, which must be eliminated to eliminate all the other bonds ".
Topic 46