Many people today within the visible church have no idea how to define sin.  They have been taught that sin is not a serious reality.  They believe that they are good people who need to deal with some personal issues.  They do not understand that they are culpable for rebellion against God's will by a failure to hear Him.  They have no idea that failure to listen to God's Word is a great sin.  They have been led astray by false teachers who discredit God's Word by their deceitful handling it.  They do not know that they are culpable for ignorance of God's Word.